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SC09 · SCIENCE THROUGH EVIDENCE

University Physics III — thermal, optical and modern evidence

All 59 finite-plan destinations are authored across thermal, entropy, optics, relativity, quantum and matter evidence, including two original composed synthesis investigations. Twenty investigation contracts,44 mixed tasks and a retained seven-version dossier support course-specific reasoning. Independent scientific and finite authored-scope review passed; authentic learner/practical evidence and institutional credit remain separate

This is the course outline. Open a unit to choose a lesson; every lesson opens on its own page. Explanations and experiments live inside those lesson pages.

Preparation and course boundaries

Preparation: Calculus-based mechanics and electromagnetism; derivatives, definite integrals, vectors, differential equations and probability-density normalization. Prior AP or algebra-based physics supports preparation but does not confer completion credit for this distinct course.

Course outcome: Integrate velocity distributions into directional pressure, distinguish flux-selected observations, reconcile heat and work with temperature-dependent state energy, and test nonideal branch and calibration assumptions. Constrained entropy, finite-source work and thermal identifiability are also taught. Coherent fields, finite-aperture integrals, Jones and imaging matrices, sampled resolution and calibration evidence are authored. Event selection, worldline proper time and relativistic conservation/inference are authored. Quantum-state normalization, moments, phase, boundary and current evidence are authored. Atomic/solid-state, nuclear-decay and detector inference are authored. Composed optical/quantum/thermal and independently anchored frequency/event investigations connect all six categories through eight unfamiliar cumulative packets.

All lessons are directly accessible. Reused foundation explanations are identified where relevant; completing a different course does not award this course's evidence. The 59 registered lessons keep separate predictions, captures, practice responses and reflections.

Kinetic distributions and thermal state evidence9 lessons

Integrate velocity and speed distributions, distinguish flux-selected observations, reconcile heat/work with temperature-dependent state energy, and test nonideal and calibrated thermal models.

Derive the speed bias of a flux-selected sample

Normalize the speed-weighted density, compare first and second moments, and freeze a threshold-tail prediction before inspecting the curve. State which detector calibration would test a speed-independent-response premise.

Test a nonideal branch before treating it as equilibrium

Compare states below, at and above the critical reduced temperature. Retain the excluded-volume domain, pressure sign and slope classification separately, and explain what additional evidence would be required for phase coexistence.

Solve a finite-body balance with unequal capacities

Bracket the root with the two starting temperatures, explain uniqueness from positive total capacity and compare a candidate midpoint residual with the solved residual. Change one initial temperature without changing the capacity law.

Entropy, irreversible processes and thermal limits8 lessons

Derive state-entropy and local generation integrals, enforce finite-reservoir constraints, distinguish heat input from net heat and test independently calibrated thermal hypotheses.

Separate entropy production from unequal body entropy changes

Derive the unique energy root, integrate both capacity-over-temperature functions and retain their opposite signs. Reject a midpoint candidate using its energy residual; explain why arbitrary plotted candidates do not establish an entropy maximum.

Wave amplitudes, aperture integrals and imaging evidence10 lessons

Integrate coherent fields and spectral envelopes, derive finite-aperture patterns and polarization projections, compose paraxial imaging matrices and separate resolution, calibration and unused evidence.

Integrate a circular-aperture response over detector samples

Reconstruct the two shifted responses, integrate central and source-coordinate pixels independently and compare widths. Retain the one-dimensional averaging boundary and identify noise or unknown brightness as additional inference requirements.

Separate diffraction scale degeneracy from an unused prediction

Fit only the three assigned orders, derive the prediction weights and propagate bounds without assuming independent random errors. Freeze the unused prediction before comparing the fourth record and distinguish a failed model check from a unique diagnosis of its cause.

Spacetime events, worldlines and conserved four-momentum9 lessons

Construct event pairs and simultaneous slices, integrate proper time, derive velocity and signal transformations, close relativistic energy/momentum and test a boost using unused bounded evidence.

Quantum evidence and introductory wave mechanics11 lessons

Compare photon and matter-wave evidence, normalize position states and their moments, and solve introductory boundary, coherent-state and scattering problems with independent calibration and unused predictions.

Separate a spectral threshold from an instrument intercept

Fit the two unknown-material records without using the generating work function or offset. Freeze the third prediction. Then add the independent reference material and recover the threshold. Change only the offset and identify which fitted quantities remain unchanged. Retain a gain-error alternative.

Derive a wavelength shift from vector momentum and total energy

Derive the shift before checking three angles, including zero and 180 degrees. Reconstruct both recoil components and compare relativistic kinetic energy with the photon loss. State what independent target-state evidence is needed before applying the free-stationary-electron model.

Connect a kinetic-energy inference to an allowed diffraction direction

Compare exact and nonrelativistic wavelengths at two energies. Hold energy fixed and change only aperture width until the first-zero existence condition changes. Retain the candidate sine even when the angle is withheld, then identify a separate energy or geometry calibration alternative.

Normalize both pieces of a continuous asymmetric amplitude

Normalize the two pieces separately, verify continuity at the peak and compare two intervals that cross different branches. Move the peak without changing L and explain why N stays fixed while interval probabilities change. State which extra information would turn this into a stationary-state problem.

Track a Gaussian phase without changing its position density

Compare beta=0,+2,−2 at the same sigma. Retain the identical position curves, equal momentum spreads for opposite chirps and opposite covariance signs. Then halve sigma and predict the momentum change before revealing it. Explain why repeated sampling does not shrink the intrinsic state width.

Obtain a discrete spectrum from two spatial boundaries

Solve the two boundary equations before selecting n. Compare n=1,2,3 at fixed L and then change L at fixed n. Integrate one interval that does not end at a node, and distinguish normalization, stationary phase and energy measurement.

Evolve interference while retaining fixed energy probabilities

Predict local probability at phases 0,π/2,π before revealing it. Integrate the cross term over the entire well to verify zero and over a half-well to see why it survives. Compare a coherent preparation with an incoherent mixture that has the same energy populations.

Find a bound state by matching a finite boundary and its tail

Derive the matching equation from both continuity conditions. Retain the initial branch bracket and numerical residual for two depths, compare energy against the infinite-wall value and independently integrate the exponential tails. State what remains uncomputed about higher states.

Use a matching solution without confusing amplitude and flux

Compare below, at and above threshold at the same width, then halve the width. Derive the threshold limit before checking it. Reconstruct a supplied unequal-lead current ratio and explain why the equal-lead shortcut cannot be exported to that problem.

Compare two spectral fits with equal data budgets and a new observation

Fit both hypotheses with exactly the same two records and freeze their third predictions. Propagate the original reading bounds with signed weights. Then design a separate left-quarter probability test and list one calibration or potential alternative that the available data still cannot exclude.

Atoms, statistical matter and nuclear evidence10 lessons

Use reduced-mass and radial-state reasoning, finite occupation sums, conditional material-response inference and nuclear population/energy ledgers; compare fresh evidence without overstating identification.

Separate relative motion from the fixed-nucleus spectral approximation

Derive the center/relative kinetic separation, calculate two finite-mass line positions and freeze the predicted difference. Add a common wavelength offset to both indications and compare the behavior of difference and ratio. Retain one unresolved multiplicative calibration alternative.

Enumerate allowed labels before making a degeneracy claim

Create a full label table for two shells and sum the magnetic labels rather than memorizing the total. Test an invalid l and identify which selected-state quantities must be withheld. Compare angular magnitude and projection without drawing a classical trajectory.

Build a fixed-number partition sum with exclusion

List all six configurations and normalize their weights for two temperature ratios. Reconstruct each level occupancy and total energy, then repeat with sixteen distinguishable configurations. Explain why a one-level occupancy greater than one would reject the spin-polarized fermion description.

Keep a band-gap interpretation conditional on transport assumptions

Fit both two-parameter families with the same two records, keeping the mobility exponent independent. Freeze their third-temperature predictions and check positivity before logarithms. Change the assumed exponent and identify which inferred parameter shifts. Retain an independent-contact or temperature-calibration test.

Turn an occupation probability into a count using the state measure

Derive the analytic count integral and check it against numerical integration. Compare 160 and 320 panels for energy, labeling the difference honestly. Change mu and theta separately and distinguish a chemical-potential-controlled calculation from a fixed-particle-number problem.

Separate binding energy, reaction energy and channel feasibility

Balance A and Z before computing Q. Compare positive and negative mass differences, identify the center-of-momentum threshold and withhold product partitions in forbidden cases. Then compute the separate binding ledger and explain why its reference state differs.

Invert a nonlinear count response before subtracting an independent background

Invert total and background means independently and show the failed subtract-first calculation. Fit the first two corrected source means, freeze the third indicated response and compare it with the supplied fresh record. State why unknown efficiency, dead time or a changing background would weaken the inference.

Reserve fresh temperatures after equal-budget heat-capacity calibration

Derive the energy and heat-capacity law from the geometric sum. Fit both amplitudes at the same temperature, retain two frozen predictions and propagate the direct calibration ratio. Then propose a temperature-dependent gain alternative and the independent measurement needed to test it.

Cross-category evidence defense and independent transfer2 lessons

Reconcile thermal, entropy, optical, relativistic, quantum and matter models across independent calibration stages; retain unfamiliar derivations, competing predictions, critique and revision without claiming real practical or learner certification.

Defend a composed optical, quantum and thermal energy account

Fit the two power standards, freeze the corrected pulse power and explicitly retain the independently supplied absorption premise. Derive the capacity integral, compare the constant-capacity alternative and calculate block entropy and absorbed mean photon count with units. Name the additional boundary information needed for total entropy production and a fresh capacity or gain observation that would challenge the chain.

Keep calibration, source inference and a new clock test in separate stages

Write the exact calibration and source records used by each fit. Freeze the independent-frequency and laboratory-duration predictions before viewing their checks. Propagate original-reading corners, identify shared-parameter correlations, and then complete a newly assigned six-category packet in the retained evidence workspace with prior exposure and assistance declared.

Investigation portfolio

Keep predictions before comparison, complete raw records and units, explain competing models and test a changed case. Supplied and simulated data are labeled in each lesson. A saved notebook is not proof of experimental technique or correct reasoning.

Distribution, collision flux and selection

Evidence to retain: Retain an anisotropic second-moment derivation, Gaussian normalization and independent cutoff/resolution checks, then derive a normalized flux-selected density and a changed threshold prediction. State what observation distinguishes bulk from detector-selected records.

Boundary: Original supplied distributions and virtual integrations. No gas handling or actual apparatus; distribution normalization does not verify equilibrium or detector response.

State functions, path integrals and finite-body balance

Evidence to retain: Differentiate the supplied activation energy, integrate a variable capacity over split intervals, compare two pressure paths between common endpoints and bracket a unique coupled-body equilibrium. Reconcile signs, units and each body energy separately.

Boundary: Positive supplied constitutive laws over finite temperature ranges, fixed-volume and quasistatic assumptions explicitly separated. No physical heating, cooling, vessel operation or measured practical evidence.

Nonideal branches and independent calibration

Evidence to retain: Retain pressure sign, excluded-volume domain, exact critical boundary and local derivative classification. Fit only assigned pressure records, freeze the unused prediction and propagate direct reading weights separately from shared-gain bounds.

Boundary: A homogeneous equation branch is not a full phase-coexistence construction. Unused generated records test internal model prediction, not independent apparatus performance or every shared bias.

State paths and isolated endpoints

Evidence to retain: Retain two reversible reference integrations with different heat/work, a nonlinear finite-body energy root and separate entropy changes, and an ideal/nonideal free-expansion comparison with a consistency identity. Freeze a changed endpoint and reject a false actual-work path.

Boundary: Supplied equilibrium constitutive laws and virtual endpoints only. No actual gas expansion, heating or practical observations. Unconstrained plotted candidates are not accessible isolated states.

Cycle budgets and finite-source work

Evidence to retain: Retain a four-leg signed heat/work table, separate positive input, test three two-reservoir claims and derive a finite-body reversible maximum from an entropy constraint. Compare direct-contact and work-extracting boundaries.

Boundary: Necessary thermodynamic conditions do not establish a working or safe device. No physical engine, pressure apparatus or performed instructional time is implied.

Entropy rate and calibrated pathway evidence

Evidence to retain: Derive local Fourier entropy production and integrate it into a boundary balance. Fit useful/leak pathways from genuinely separate records, freeze two changed-temperature predictions and retain direct correlated-error propagation plus a shared-gain limitation.

Boundary: Synthetic steady profiles and supplied power records, not measurements. Local equilibrium and response-family assumptions must remain visible; first-fit data are not fresh validation.

Coherent amplitude, spectrum and interface derivations

Evidence to retain: Retain complex field sums and visibility extrema; independently integrate the rectangular spectral phase; sum reflected beams and verify zero-thickness/matched-index limits and power closure.

Boundary: Original virtual lossless/coherent packets; no laser, intense-light source, alignment or practical apparatus operation.

Aperture transforms and polarization inference

Evidence to retain: Derive aperture integral/central limit, separate fringe/envelope scales, enumerate missing orders, verify finite-array period power and compare both orders of complex Jones projection.

Boundary: Scalar far-field and ideal monochromatic polarization assumptions; no copying of algebra-based course credit or actual experimental validation.

Imaging, sampling and independent calibration

Evidence to retain: Compose matrices and propagate an actual ray family; integrate a supplied circular-response cut over pixel intervals; freeze a three-order fit and propagate exact linear-weight bounds before unused comparison.

Boundary: Paraxial ray model and one-dimensional sampled response are distinct approximations. Hard bounds are not confidence intervals, and unused synthetic data are not an independent physical measurement.

Events, simultaneous slices and path-dependent clock readings

Evidence to retain: Transform three causal classes and invert the map; explicitly select simultaneous endpoint pairs in two frames; integrate two returning worldlines and verify equal endpoints but unequal proper times.

Boundary: Original flat-spacetime coordinates and idealized paths, not a real clock experiment or physical instantaneous reversal.

Differentials, signals and conserved energy-momentum

Evidence to retain: Derive velocity from transformed increments; close invariant mass, collision internal/bulk energy, photon recoil and arrival-time ledgers. Reconstruct a changed packet before public feedback.

Boundary: No actual particle source, radiation, accelerator, propulsion or laboratory procedure; c=1 numerical units retain distinct physical dimensions.

Training-frame inference and unused bounds

Evidence to retain: Freeze a boost interval inferred from a measured event-difference ratio, derive monotonic spatial and stationary time extrema, then compare independent unused coordinate intervals without refitting.

Boundary: Original hard-bound packet; marginal overlap is a necessary screen, not universal joint compatibility, probability or independent clock certification.

Photon and matter-wave calibration comparison

Evidence to retain: Fit a stopping line from two records, freeze a third and then use an independent reference material to separate offset and threshold. Derive Compton shift from vector momentum and relativistic energy. Compare exact/nonrelativistic electron wavelength and reject an unsupported aperture angle.

Boundary: Synthetic single-particle and instrument models; no ultraviolet, radiation, electron-beam or vacuum operation. Reference calibration and target-state assumptions are independent premises, not conclusions of a fit.

Normalization, phase and probability notebook

Evidence to retain: Normalize a piecewise amplitude with physical dx, integrate asymmetric moments, compare equal position densities with different phase chirps, derive well boundaries and integrate a coherent local probability. Contrast an incoherent mixture with the same energy populations.

Boundary: Original supplied quantum states and ideal Hamiltonians. Probability density, intrinsic spread, sampling error and individual trajectories remain distinct; no performed state preparation is claimed.

Matching, current and fresh spectral evidence

Evidence to retain: Bracket the lowest finite-well matching root and normalize both tails. Derive the barrier threshold limit and compare amplitude with current transmission. Fit two spectral alternatives with equal calibration budgets, freeze the third-level predictions and propagate the direct shared-record bounds.

Boundary: One-dimensional nonrelativistic matching models; no unique potential reconstruction, tunneling time or hardware evidence. Numerical brackets are floating-point diagnostics and bounded input errors are not statistical confidence.

Mass, radial measure and exclusion

Evidence to retain: Derive the reduced-mass shift for a changed mass pair, retain a common-offset alternative, integrate a changed radial sphere and enumerate a changed finite canonical state packet. Predict the difference between spatial mode, shell mode, mean and exclusion-limited occupancy before checking.

Boundary: Hypothetical Coulomb and finite-level states; no actual isotope identification, atomic imaging or spin preparation. State count is not occupancy.

Occupation integrals and competing transport models

Evidence to retain: Fit activation and contact families using the same two temperature records and independently fixed mobility exponent; freeze the third prediction. Integrate a bounded DOS with two quadrature resolutions, then calibrate classical and quantum heat-capacity amplitudes with one shared datum and compare unused temperatures with direct bounds.

Boundary: Conditional original response families, not measured band structure. A numerical resolution difference is not a certified quadrature error bound; fixed chemical potential is not fixed particle count.

Inventory, channel energy and calibrated detector response

Evidence to retain: Balance an abstract reaction ledger and reject a negative available-energy channel. Derive equal and unequal Bateman rates, check population versus activity at a peak, then correct synthetic steady-replica total/background means separately before fitting two ages and predicting a fresh third.

Boundary: Fictional mass and population records, virtual detector means only. No isotope activity/dose, reaction probability, real detector statistics or performed practical claim.

Optical-to-thermal boundary defense

Evidence to retain: Fit independent optical standards,freeze pulse power and absorption premises,derive a finite-capacity temperature and entropy change,convert photon energy consistently,and compare a constant-capacity or gain alternative with a newly assigned packet.

Boundary: No physical source or material procedure. Block entropy change is not total entropy generation; exposed generated checks are not real measurements.

Independent calibration and unfamiliar six-category audit

Evidence to retain: Fit only independent frequency anchors,freeze an unused calibration record,infer a Doppler parameter from a separate source and freeze an independent clock-duration test with original-reading corner bounds. Then complete a reviewer-frozen six-category assignment with retained first reasoning,actual criterion critique,revision and assistance/exposure declarations.

Boundary: Conditional affine response and flat-spacetime premises; deterministic corner bounds are not probabilities or a universal simultaneous-calibration certificate. Actual learner response and supervised practical gates remain separate.

Mixed assessment and cumulative project

Open the retained response and project workspaces. Practice, saved work and independently reviewed proficiency remain separate.

Mixed assessment and retained reasoning

These 44 course-specific public tasks are practice, not a secure examination. Each retains up to three immutable written responses, known feedback exposure before each response, and human rubric critiques. Drafts remain editable. No text-length check or self-reported review certifies correctness, independence, laboratory skill or mastery.

1. Equal means, unequal wall accounts

Independent uniform velocity components have half-widths 300,200,100 m/s and mass density0.6 kg/m³. Derive all three normal pressures and translational energy density from integrals. If isolated relaxation at fixed density preserves only the total kinetic energy and becomes isotropic, find its scalar pressure. Explain why that number is not the original x-wall pressure.

Course-specific review criteria

  • Derive the incoming collision-flux integral or equivalent second moment.
  • Distinguish mean from mean square and directional from scalar pressure.
  • Preserve the stated density and total-energy constraint.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

2. Two normalized populations at one thermal scale

At thermal scale s=300 m/s, compare bulk Maxwell mode,mean and RMS with the flux-selected mean and RMS. Derive the emitted tail above600 m/s and the ratio of emitted to bulk mean translational energy. Does that ratio prove the emitted sample came from a hotter reservoir? State why a finite Simpson normalization and a rigorous probability-tail bound address different errors.

Course-specific review criteria

  • Normalize the flux-weighted law rather than relabel the bulk law.
  • Retain correct moments, squared-speed energy and threshold units.
  • Separate selection and numerical-error mechanisms.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

3. A mode interpolation and a state integral

For supplied Cv/R=1.5+T²/(T²+theta²), find Cv/R at T=400 K,theta=200 K and differentiate the taught energy primitive to check it. Separately two moles with Cv=20+0.01T J/(mol K) warm from300 to600 K at fixed volume. Find exact energy, the initial-capacity estimate, missed correction and the two contributions when split at400 K.

Course-specific review criteria

  • Keep the illustrative activation law separate from exact quantum mode populations.
  • Integrate molar capacity with amount and units.
  • Show split-interval additivity and explain Q=delta U only under the stated work boundary.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

4. Do not confuse a mathematical path with a stable branch

An ideal monatomic gas starts at1 litre,100 kPa and ends at2 litres,50 kPa. Find work and heat along an isotherm and along the straight pressure-volume line. Separately the reduced van der Waals model has t=.9,v=1: compute pressure,slope and formal compressibility, and decide what they establish. Compare with t=v=1.

Course-specific review criteria

  • Integrate each specified path and retain first-law sign conventions.
  • Separate ideal-gas endpoint energy from the unrelated nonideal packet.
  • Distinguish formula domain, local stability and global phase equilibrium.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

5. Find a root before assigning a heat-transfer account

Bodies with CA(T)=2+.01T J/K and CB=4 J/K start at400 and200 K under the taught isolated fixed-volume boundary. Derive the equilibrium equation and prove uniqueness between the initial temperatures. Compute the equilibrium and each body energy change. Would the result also establish the equilibration time or actual insulation?

Course-specific review criteria

  • Integrate each capacity from its own starting state.
  • Bracket the positive root and justify uniqueness.
  • Close signed energy and distinguish state from rate or apparatus claims.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

6. A third record tests a family, not a shared gain

Indicated pressures at1 and2 litres are16 and7 kPa. Fit Kfit/V+Afit/V² and freeze a3-litre prediction. Compare the ideal one-parameter fit using only the first record. Each calibration indication has independent deterministic error bounded.03 kPa; derive the direct third-prediction bound. If gain is independently bounded.98..1.02, find a gain-only interval for physical K and explain what that interval omits.

Course-specific review criteria

  • Keep model fitting and fresh validation roles explicit.
  • Recover indicated coefficients without asserting they are physically calibrated.
  • Propagate direct shared-observation weights and state conditional versus combined intervals.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

7. Same endpoint, different heat

A gas has total Cv=15 J/K, nR=10 J/K. Endpoints are T1=300 K, V1=2 L and T2=600 K, V2=3 L. Compare fixed-volume heating then final isothermal expansion with initial isothermal expansion then heating: find delta S, delta U and both heats. Does either reference path prove the actual history was reversible?

Course-specific review criteria

  • Integrate with dimensionless logarithms and correct total capacities.
  • Keep state changes separate from path-dependent heat/work.
  • Do not identify a mathematical reference with an unknown actual history.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

8. Two ways to reach a common temperature

Two constant-capacity bodies Ch=3 J/K, Cc=1 J/K start at 800 K and 200 K. Compare direct isolated contact with a reversible cyclic engine between them. Find both common temperatures, direct-contact entropy production and maximum extracted work. Explain why the lower endpoint does not violate energy conservation.

Course-specific review criteria

  • Apply energy conservation to contact and entropy conservation to reversible extraction.
  • Weight logarithms by the actual unequal capacities.
  • Retain exported work and distinguish a limit from actual performance.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

9. A consistent alternative to constant-temperature expansion

A supplied gas has U=20T−A/V joule and p=10T/V−A/V² kPa, V in litres, A=400 J L. It expands freely inside an insulated rigid enclosure from 400 K, 1 L to 4 L. Verify the consistency identity, find T2 and delta S, and compare the ideal A=0 prediction.

Course-specific review criteria

  • Check the linked pressure/internal-energy laws rather than mixing incompatible models.
  • Use the actual zero-work boundary and a reference entropy integral.
  • Distinguish zero energy change from constant temperature.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

10. Energy closure does not supply the input denominator

A monatomic ideal gas makes the clockwise rectangle p_low=80 kPa, p_high=240 kPa, V_low=1 L, V_high=3 L. Find each signed heat, net work and efficiency. Separately a cyclic device absorbs 900 J from 750 K and rejects to 300 K while claiming 600 J work. Test both laws for that separate device.

Course-specific review criteria

  • Use Cp versus Cv leg accounts with signs and kPa L conversion.
  • Divide by positive heat input, not net heat.
  • Test the separate claim with absolute temperature and a cyclic boundary.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

11. A steady entropy balance with local variation

A steady slab has k=3 W/(m K), area 0.4 m², length 2 m and boundary temperatures 500/250 K. Derive the linear profile, heat rate, local entropy-production density and total generation. What changes when length doubles with the same boundaries?

Course-specific review criteria

  • Include area only when integrating density or obtaining total heat rate.
  • Distinguish boundary entropy flux, generation and storage.
  • Retain the changed geometric scaling rather than a fixed-gradient assumption.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

12. A fresh temperature and shared fit errors

With cold/ambient 300 K and hot 400 K, heater reads 360 W and independent cold calorimeter 240 W. Fit linear K, L. Freeze heater predictions at 550 K for a linear leak and for a quadratic leak L(deltaT)²/(100 K), both matching calibration. Each first reading has absolute error≤3 W; find K, L error bounds and the direct linear prediction bound. A fresh heater reading is 905±4 W: is it consistent with the linear prediction under these bounds?

Course-specific review criteria

  • Use the independent cold observation to separate pathways.
  • Freeze both hypotheses before inspecting the fresh record.
  • Propagate direct reused-record weights and add fresh-reading bound without calling it a confidence interval.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

13. Distinguish amplitude imbalance from spectral averaging

First packet: coherent beam intensities 1 and 4, phase 180°. Derive intensity, extrema and visibility. Separate equal-beam flat-spectrum packet: carrier 10, full width 1, delay 0.5 in the stated units. Integrate normalized spectral phase and calculate the recorded intensity and visibility. Why can the two contrast mechanisms not be collapsed into one unexplained loss factor?

Course-specific review criteria

  • First intensity1, extrema1/9 and visibility0.8 from amplitudes1/2.
  • Second μ=2/π, intensity2+4/π≈3.27324 and visibility2/π; retain carrier phase10π.
  • Different amplitude-balance versus spectral-delay mechanisms; phase average and fixed reading distinguished.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

14. Keep reflection phase, propagation and aperture normalization distinct

Film indices1/1.5/1 with vacuum wavelength600 nm and thickness200 nm: derive interface coefficients, round-trip phase and full R/T. Separately a normalized uniform slit has width3 and spatial frequency0.5. Derive field and intensity from the aperture integral. Do either local cancellation results prove that the source emits no power?

Course-specific review criteria

  • Film r01−0.2,r12+0.2,phase2π,R0,T1 in the exact lossless series.
  • Slit field−2/(3π), intensity4/(9π²)≈0.0450316; first zero1/3.
  • Reflected cancellation sends flux into transmission; normalized slit shape is not total source/throughput power.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

15. Combine finite spatial sums without confusing vector order

Original double slit w3,d4: find fringe spacing, first envelope zero and first missing order. Separate six-slit narrow array at q0.5: find sum and principal peak/nearest-zero spacing. For Jones input (1,−1)/sqrt2, compare45° then horizontal polarizers with the reverse order.

Course-specific review criteria

  • Fringes1/4, first envelope zero1/3, first missing order4 at u1.
  • Six alternating phasors sum0; principal intensity36 and nearest zero1/6 in q, principal spacing1.
  • Forward Jones intensity0, reversed0.25; operators generally do not commute.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

16. Separate geometric focus from sampled wave resolution

For f10 cm,a40 cm,b20 cm, multiply P(b)L P(a), compute determinant and the image-plane distance. For object height0.1 cm and angles−0.02,0,+0.02 rad, find sensor heights. Then explain why setting B=0 would not establish perfect resolution of two circular-aperture images. State the exact one-dimensional pixel operation and the additional evidence needed for a real two-source decision.

Course-specific review criteria

  • MatrixA−1,B−20 cm,C−0.1/cm,D−3, determinant1; image plane40/3 cm.
  • Sensor heights0.3,−0.1,−0.5 cm, spread0.8 cm.
  • B0 removes initial-angle dependence only in the paraxial ray model; diffraction and sampling remain.
  • Pixel is width-normalized interval integral of two incoherent intensity responses; noise, brightness, calibration and decision criteria remain unspecified.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

17. Propagate common calibration and unused-record bounds

Fit only orders1/2/3 at6.4/12.4/18.4 mm. With gain anchor0.8±0.01 and each reading bound0.06 mm, derive slope/intercept, nominal wavelength and hard endpoints. Predict order4 before comparing24.6±0.06 mm. Does changing the gain anchor alter this held-out prediction in mm?

Course-specific review criteria

  • Slope6,intercept0.4; wavelength750 nm, lower594/0.81≈733.3333 and upper606/0.79≈767.0886 nm.
  • Held-out prediction24.4±0.14 mm using weights−2/3,1/3,4/3; intervals touch at24.54 mm.
  • The gain changes inferred wavelength but not same-coordinate fitted prediction; shared systematic and unused comparison are distinct.
  • Compatibility under hard bounds is not a confidence level, unique-model proof or actual calibration certification.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

18. Freeze a discriminating optical evidence plan

Before public feedback, choose a contrast, aperture or imaging claim and an alternative involving calibration, phase, source state or sampling. Define a virtual record that distinguishes them, an unused prediction, units and finite uncertainty. Derive at least one amplitude/integral/matrix relationship rather than importing a previous algebraic answer. No physical source or instrument procedure is requested.

Course-specific review criteria

  • Original claim, alternative and different predicted records retained.
  • Explicit amplitude/integral/matrix derivation and approximation domain.
  • Independent versus shared calibration, unused evidence and uncertainty retained.
  • First report, actual critique, justified revision and unfamiliar response remain genuinely required.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

19. Retain the event pair before naming its observable

Transform event difference (3,5) at β 0.8 in c=1 units; classify its interval and explain the reversed time order. Separately a rod has rest length 6 and laboratory speed 0.6. Construct lab-simultaneous and rest-simultaneous endpoint pairs and report which spatial difference measures laboratory length.

Course-specific review criteria

  • γ 5/3, transformed(−5/3,13/3), invariant −16, spacelike/no causal reversal.
  • Lab simultaneous length 4.8, whose rest differences are (−3.6,6).
  • Rest-simultaneous pair transforms to lab(4.5,7.5), not a simultaneous lab length.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

20. Integrate a path and transform an independent differential

For T 10, a 0.6, derive proper times for the fixed-speed round trip and v(t)=a(1−2t/T). Then independently transform dt′ 1, dx′−0.5 from a frame moving +0.6. Compute dt, dx, u and check the interval. Why does neither zero net trip displacement nor a Galilean sum supply the required answer?

Course-specific review criteria

  • Piecewise proper time 8; varying path(10/2)[0.8+asin(0.6)/0.6]≈9.362509.
  • Transformed dt 0.875, dx 0.125, u 1/7; increment invariant 0.75.
  • Worldline integral uses instantaneous speed; velocity transformation changes both coordinate increments.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

21. Separate incoming particle invariants from composite internal energy

A mass 2 particle moves at 0.6: derive E, p, K and classical kinetic error. Separately a unit-mass projectile at 0.6 joins a stationary target of mass 2 with no escaping products. Find final total energy/momentum, composite mass/speed and internal versus bulk kinetic energy.

Course-specific review criteria

  • Particle E 2.5, p 1.5, K 0.5, classical 0.36,28% underestimate; invariant 4.
  • CollisionE3.25,p0.75,M=sqrt10≈3.162278,speed3/13.
  • Internal increment sqrt 10−3≈0.162278, bulk kinetic 3.25−sqrt 10≈0.087722; sum 0.25.
  • No velocity-dependent rest-mass claim for unchanged incoming particles; final composite is a different internally excited system.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

22. Keep photon recoil separate from photon arrival timing

An initially stationary emitter M 3 loses rest-mass fraction 0.1 into one +x photon and one body. Derive photon energy, body rest/total energy, recoil momentum and kinetic energy. Separately a receding source β 0.8 emits with proper period 2. Find laboratory emission and arrival intervals and frequency ratio; distinguish its clock-rate ratio.

Course-specific review criteria

  • Final rest mass 2.7, photon 0.285, body total 2.715, recoil momentum −0.285 and kinetic 0.015.
  • Energy 3 and net momentum 0; rest decrease 0.3 is not all photon energy.
  • Emission interval 10/3, extra delay 8/3, arrival 6; frequency ratio 1/3 versus clock ratio 0.6.
  • Formal separate packets, not a real transition or a cosmological-redshift inference.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

23. Preserve a boost fit and its unused event test

Training event-difference ratio for a clock at rest in S is −0.6±0.02 in S′; absolute increments are not given. Infer boost bounds. For unused S pair (5,3), derive extrema of transformed coordinates over those bounds, then compare reported S′ pair (4,0.2) with coordinate hard errors ±0.05. Explain the role of an interior stationary point and why a central invariant discrepancy alone is not exact evidence of a violated invariant.

Course-specific review criteria

  • Boost 0.58..0.62, central unused prediction (4,0).
  • Spatial bounds≈−0.127453..0.122757; time minimum 4 at β 0.6, maximum≈4.002030.
  • Spatial measured interval 0.15..0.25 is disjoint, rejecting the declared training/model/bound combination.
  • Hard uncertainties and incomplete compatibility screen retained; no refit or interpretation as a confidence probability.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

24. Freeze a frame-aware discriminating inference

Before public feedback, choose a clock, length or collision claim and a competing explanation involving event selection, frame sign, calibration or escaping energy. Specify a virtual unused record, derive its prediction, retain units and finite uncertainty, and plan actual critique/revision plus genuinely unfamiliar first reasoning. Do not propose physical source operation.

Course-specific review criteria

  • Original event definitions, frame direction and competing prediction.
  • At least one invariant, integral or conservation derivation and independent check.
  • Training versus unused evidence and shared uncertainty preserved.
  • First report, real critique, reasoned revision and unfamiliar response not fabricated.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

25. A threshold reference and a recoil account

Use a rounded stopping slope 0.4 V per frequency unit. Unknown-material indications at f8 and10 are1.3 and2.1 V; an independent reference with work function3 eV indicates1.2 V at f10. Fit the unknown line, freeze f12, and separate offset/work function. Separately a100 keV photon backscatters from a free stationary electron of rest energy511 keV; find outgoing photon energy and recoil kinetic energy. Why does an electron aperture use lambda=h/p rather than hc/K?

Course-specific review criteria

  • Give the unused frequency a frozen prediction.
  • Use the reference only to resolve the intercept ambiguity.
  • Close both recoil energy and momentum with the correct rest-energy convention.
  • Distinguish massive-particle kinetic energy from photon total energy.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

26. A probability peak is not its mean or mass

A triangular amplitude has support length2 nm and peak fraction q=.25. Derive its normalization constant and probability left of x=1 nm. Separately the supplied beta-family density has p=3 on u0..1: derive mean,second moment,variance and mode. State why neither density alone specifies momentum statistics.

Course-specific review criteria

  • Keep dx=L du in normalization.
  • Use the correct branch for the interval endpoint.
  • Distinguish first/second moments and density maximum.
  • Retain phase as missing information.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

27. A chirp and a changed hard-wall length

For Gaussian sigmaX=.4 nm,beta=−1, find sigmaP/hbar in nm⁻¹, uncertainty product divided by hbar and covariance divided by hbar. Compare100 independent position preparations. Separately an electron well has L1.5 nm,n3 and energy coefficient.3760301626 eV nm²: find energy,interior nodes and left-third probability.

Course-specific review criteria

  • Retain the quadratic-phase contribution and covariance sign.
  • Separate state spread from standard error of a mean.
  • Use both wall conditions and n²/L² scaling.
  • Integrate interval density rather than use a uniform shortcut.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

28. Same energy population, different local probability

For the equal n1/n2 coherent well state, derive probability in the left quarter for relative phase0 andpi. Compare an incoherent equal mixture and compute mean energy in units E1. Which observation distinguishes the phase-coherent state from that mixture?

Course-specific review criteria

  • Retain the local cross term and its sign.
  • Use orthogonality only over the appropriate full interval.
  • Distinguish energy populations from position interference.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

29. Normalize a matched tail and keep current factors

A finite symmetric well has an even matching solution z=pi/4,kappa a0=pi/4. Verify the match,find E/V0 and exterior probability from the taught normalization. Separately an equal-lead rectangular barrier at E=V0 has width parameter2; find T. For a different unequal-lead packet, transmitted amplitude squared .6 and right/left wave-number ratio.25 are supplied: find current transmission.

Course-specific review criteria

  • Keep the well-bottom energy reference and both tails.
  • Use the exact barrier threshold limit.
  • Do not transplant an equal-speed amplitude shortcut.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

30. Equal fitting budgets and a separate spatial test

Two spectral indications are y1=2,y2=5 eV at levels1,2. Fit quadratic-in-n and affine-in-n families and freeze their n3 predictions. Each input has independent hard bound±.02 eV. A fresh level reads10.02±.01 eV: compare each residual with its own combined bound. Separately compare uniform and ground-well density probabilities in the left quarter. Does a surviving model establish a unique potential?

Course-specific review criteria

  • Use exactly the same fitting records for both two-parameter families.
  • Propagate direct prediction weights, then add fresh error.
  • Keep spectral and spatial tests separate.
  • Limit uniqueness and calibration claims.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

31. A common offset and an independently scaled sphere

An ideal infinite-mass line wavelength is 600 nm. Nuclear/electron mass ratios are 1500 and3000; a common unknown additive wavelength indication offset is present. Find both physical wavelengths and heavy-minus-light difference; say what the offset cancels from and what a gain error would change. Separately a1s radial state has scale.08 nm: find mean radius, shell mode and probability inside.16 nm. Count spin-orbitals for principal shell n=3 and reject l=3 there.

Course-specific review criteria

  • Use reduced rather than electron-only mass.
  • Separate differential offset cancellation from multiplicative calibration.
  • Integrate shell measure and distinguish its mode from mean.
  • Enforce complete label domains.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

32. Different counting rules on the same four energies

Two spin-polarized fermions occupy four nondegenerate states0, delta, 2delta, 3delta at q=exp(−delta/kBT)=1/2. Enumerate six pair weights, find the ground occupancy and total mean energy in units delta. Compare the ground occupancy for two distinguishable particles. Separately a constant DOS3 states/eV spans0 to 8 eV with mu=4 eV: find occupied count at any positive temperature and explain why f(mu)=1/2 is not itself that count.

Course-specific review criteria

  • Keep fixed N and exclusion before assigning thermal weights.
  • Normalize configurations, not just one-particle probabilities.
  • Distinguish DOS measure from occupation.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

33. A prefactor that changes an inferred activation slope

Log conductivity readings at 300 and600 K are−2 and ln(2)−1. Independently stipulated mobility exponent p=1. Fit A and Theta for L=A+p ln(T/300)−Theta/T, then freeze L at 900 K. What apparent Theta follows if p is incorrectly set to zero? Fit the same two records with resistance C+D/T and determine whether its900 K prediction is positive. Does either fit alone establish a unique band gap?

Course-specific review criteria

  • Use the stipulated exponent rather than the generating answer.
  • Give both alternatives the same two calibration records.
  • Check resistance positivity before logarithms.
  • Keep a band-gap claim conditional.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

34. A fictional reaction and a different daughter lifetime

Use the abstract (12, 6)+(4, 2) to(15, 7)+(1, 1) ledger. Rest-mass difference is−.004 u with 931.5 MeV/u and incoming center-of-momentum kinetic energy 5 MeV. Test feasibility and partition final energy with approximate mass ratio 15:1. Separately a chain has initial parent 800, daughter 0, lambda1=.1/min, lambda2=.2/min and time ln(2)/.1 min. Find parent, daughter, stable populations and both activities.

Course-specific review criteria

  • Close nucleon/charge and energy accounts separately.
  • Name the center-of-momentum and nonrelativistic approximation.
  • Use the correct daughter source term and rate units.
  • Distinguish activities from populations.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

35. A nonlinear response with an independently calibrated background

For separately steady replicas, calibrated tau=.001 s. A background-only indication is 1000/51 per second. Total indications at nominal ages0 and2 s are 1000/11 and3000/53 per second. Correct all three means, fit the exponential source amplitude and rate, and freeze the total indicated rate at nominal age4 s. Explain why subtracting indications before inversion is wrong and why output count uncertainty is not automatically Poisson.

Course-specific review criteria

  • Invert total and background separately within saturation domain.
  • Fit only the first two source means.
  • Forward-transform the fresh total prediction.
  • Distinguish steady replicas from an exact changing-source finite-window model.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

36. A ratio-bound comparison without borrowing a fresh reading

An independently fixed oscillator Theta gives supplied factors Fcal=.8, Flow=.3, Fhigh=.95. The sole amplitude-calibration indication is 1.6±.02 response units. Freeze quantum and classical predictions at both fresh temperatures and their calibration-only hard bounds. Fresh low response is.61±.01. Assess each family under those bounds and name an unresolved gain alternative. Separately explain why a Fermi calculation at fixed mu need not preserve particle number.

Course-specific review criteria

  • Use one fitted amplitude per family.
  • Propagate the direct positive calibration ratio.
  • Add fresh error only after freezing predictions.
  • Distinguish rejection of a family from unique mechanism proof.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

37. An unfamiliar directional pressure packet

Independent uniform velocity components have zero means and half-widths100,200,300 m/s at mass density1.2 kg/m³. Derive all directional normal pressures and translational energy density from moments. If energy-preserving relaxation at fixed density becomes isotropic, find its pressure. Separately explain why effusive speed weighting cannot be interpreted as a hotter reservoir without correcting selection.

Course-specific review criteria

  • Integrate each squared component rather than squaring its zero mean.
  • Retain density and the half-trace energy relation.
  • Separate directional initial pressure from isotropic final pressure.
  • Identify flux selection as a change of sampling measure.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

38. Direct contact versus reversible extraction

Two isolated bodies each have constant total heat capacity2 J/K,initial temperatures600 and300 K. Compare direct thermal contact with ideal reversible work extraction ending at a common temperature. Derive final temperatures,total entropy change for direct contact and maximum extracted work. State which external energy/entropy boundary assumptions differ.

Course-specific review criteria

  • Conserve energy for direct contact.
  • Conserve total entropy for the reversible limiting process.
  • Use absolute temperatures and full finite-source evolution.
  • Do not use initial Carnot efficiency for all transferred energy.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

39. Aperture zeros and ordered polarization

For a uniform rectangular aperture,derive normalized far-field amplitude by integrating exp(iqx) over a symmetric width and show its first zero. Two equal apertures have center spacing three times their width: which noncentral interference order first coincides with an envelope zero? Separately a horizontally polarized input passes ideal45-degree then vertical polarizers; find transmitted fraction. Reverse the first element to vertical and explain the change.

Course-specific review criteria

  • Integrate amplitude before squaring.
  • Distinguish aperture envelope zeros from interference maxima.
  • Compose ordered projections rather than add angles.
  • Keep coherent,far-field and ideal-polarizer premises.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

40. An event pair and a separate recoil ledger

In c=1 units transform event difference(dt,dx)=(5,3) to a frame moving beta=.6. Classify the invariant and interpret the proper interval. Separately an emitter initially at rest with mass4 emits one +x photon and leaves a body of rest mass3. Find photon energy,recoil momentum,body total and kinetic energies; keep the two packets separate.

Course-specific review criteria

  • Transform both coordinates for the same event pair.
  • Use the invariant and identify a rest-frame pair.
  • Close photon and body energy-momentum together.
  • Do not equate rest-mass decrease with photon energy alone.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

41. An asymmetric state, a chirp and a threshold limit

A triangular amplitude on length L has peak fraction q=.75. Derive probability left of x=.5L and its normalization constant. Separately a normalized Gaussian has chirp beta=sqrt(3): find uncertainty product/hbar,covariance/hbar and covariance-corrected determinant/hbar². For an equal-lead barrier at exact threshold and width parameter3,find current transmission.

Course-specific review criteria

  • Keep the correct triangular integration branch and physical length.
  • Include phase-induced covariance rather than claim all Gaussians minimize the simple product.
  • Use the analytic threshold limit and equal-lead premise.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

42. Unequal decay rates and an occupation measure

A chain begins with1000 parents and no daughters. Parent rate is.4/min,daughter rate.2/min. At u=lambdaParent t=ln4,derive all populations and both activities; explain the daughter maximum. Separately a constant finite DOS4 states/eV spans0 to2 eV with mu1 eV. Find occupied number at any positive temperature and explain what would change in a fixed-number rather than fixed-mu calculation.

Course-specific review criteria

  • Use the sourced daughter equation and unequal-rate solution.
  • Keep population versus activity and rate units distinct.
  • Integrate the DOS measure and use band symmetry.
  • Do not infer material identity from a finite supplied DOS.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

43. A new calibrated pulse and a finite-body check

Independent power standards10 and50 W indicate9 and33. A pulse indicates18.6 for10 s; independently justified absorption fraction.8. Use initial300 K and C(T)=2+.01T J/K. Fit power calibration,find incident/absorbed energy,final temperature and block entropy change. At supplied photon energy2.5 eV and conversion1.6e−19 J/eV,find absorbed mean photon count. Can the full entropy production be inferred?

Course-specific review criteria

  • Fit gain/offset only from standards.
  • Keep unabsorbed energy outside the block heat account.
  • Integrate capacity and entropy rather than use one temperature.
  • Separate mean photon count from actual detected count and total entropy generation.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

44. A fresh frequency and a separately timed worldline

Frequency anchors2 and6 indicate2.7 and7.5. Before further data,freeze the indication expected at independent frequency4. A receding source with independently known rest frequency5 indicates3.3. Infer corrected source frequency,Doppler ratio,beta and laboratory duration for independently known proper duration6. Contrast the pulse arrival interval. State how original-reading bounds and a new six-category task should be retained before feedback.

Course-specific review criteria

  • Preserve independent anchor,source and fresh-record roles.
  • Correct both gain and offset before forming a ratio.
  • Distinguish event duration from pulse arrivals.
  • Retain original correlated error inputs and an actually new assignment,not a public-key claim.

Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.

0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.

Retain a criterion-by-criterion human review

Reviewer identity and role are declarations, not authenticated credentials. Unsaved review fields below are lost on navigation. Review every criterion with an exact quotation, calculation or evidence citation and a next step.

Six-category classical and modern evidence defense

Final synthesis proposal for the finite59-destination SC09 course. Coordinator retains all actual thermal,entropy,optical,relativistic,quantum and matter milestones and predecessor definitions; these concise domain milestones retain their actions while exact earlier definitions and learner histories remain archived; completion is never awarded automatically.

  1. Thermal distributions and state evidence

    Retain the original distribution-to-pressure integral, Maxwell cutoff and resolution comparison, effusive selection normalization, variable-capacity state integral, two path-work accounts, nonideal branch decisions and independently calibrated pressure prediction. Reconstruct the new directional-moment exit packet before feedback.

    Evidence to retain: Actual prior thermal derivations and records, preserved first reasoning, changed model checks and source/domain qualifications.

  2. Entropy constraints and finite-source limits

    Retain reference-path entropy, finite-body constrained equilibrium, free-expansion model comparison, complete cycle heat/work ledger, reversible finite-source limit, local entropy-production versus boundary flux, and original-reading inference bounds. Defend the new direct-contact versus work-extraction packet.

    Evidence to retain: Signed energy/entropy ledgers, absolute temperatures, reversibility and boundary premises, unused predictions and unresolved alternatives.

  3. Optical amplitude and inference evidence

    Retain coherent complex-field and finite-bandwidth evidence, film phase limits, aperture integral, double-slit envelope and finite-array distinctions, ordered Jones projections, imaging matrix, sampled resolution and calibration covariance. Derive the new missing-order and polarizer-order exit packet.

    Evidence to retain: Original amplitude/integral/matrix work, independent versus shared calibration, source state, sampling limits and fresh optical predictions.

  4. Relativistic event and conservation evidence

    Retain selected event pairs, simultaneous endpoint constructions, worldline proper-time integrals, transformed differentials, invariant energy-momentum, collision/recoil budgets, arrival timing and unused boost bounds. Reconstruct the new timelike-pair and photon-recoil packet.

    Evidence to retain: Actual event definitions and frame signs, invariant checks, internal versus bulk energy, original-reading uncertainty and unused records.

  5. Quantum state and boundary evidence

    Retain reference-assisted stopping calibration, vector Compton conservation, matter-wave aperture existence, piecewise normalization and moments, chirped Fourier covariance, hard-wall and finite-well matching, coherent local probability, current transmission and equal-budget spectral tests. Solve the new asymmetric-state/chirp/threshold packet.

    Evidence to retain: Original normalization and matching derivations, correct physical measures, phase and Hamiltonian limits, independent references and fresh comparisons.

  6. Atomic, statistical and nuclear matter evidence

    Retain reduced-mass and radial-state derivations, angular label counts, canonical exclusion, activation/contact alternatives, bounded DOS integrals, nuclear mass/energy ledger, unequal/equal-rate chains, calibrated detector/background response and classical/quantum thermal comparison. Solve the new daughter-activity and finite-band packet.

    Evidence to retain: Actual counts and measures, conditional transport interpretation, energy/population/rate closure, numerical diagnostics and withheld temperature or age predictions.

  7. Defend both composed calibration chains

    Use the new10/50 W standards and18.6 pulse indication packet,derive the finite-capacity and photon budgets,and retain missing entropy-boundary information plus one independently testable alternative. Separately use the new2.7/7.5 frequency anchors,freeze the independent frequency test,infer the source speed and derive event-duration versus arrival predictions. Propagate original-reading errors rather than independent fitted-parameter guesses.

    Evidence to retain: Unchanged first responses,exact independent/fitted/fresh data roles,calibration fits,signed energy/entropy boundaries,corner or monotonic bounds,event definitions,limitations and frozen changed predictions.

  8. Complete a genuinely new six-category defense

    An actual reviewer freezes an unfamiliar packet spanning thermal moments,entropy constraints,optical amplitude or matrix reasoning,relativistic events,quantum normalization/boundaries,and matter energy or population inference. Preserve first work,obtain criterion-linked critique,revise reasoning and then answer a different separately frozen transfer assignment. Declare prior exposure and assistance.

    Evidence to retain: Actual first report,reviewer identity/role and evidence-linked critique,reasoned revision,exact new assignment and separate response. Test fixtures and public examples are never labeled real learner performance.

Project review criteria

  • Thermal distributions and flux-selection measures are normalized and integrated correctly.
  • Energy state/path accounts and entropy constraints keep exact boundary and reversibility premises.
  • Optical amplitude,aperture,polarization or imaging calculations retain coherent/sampling limits.
  • Relativistic event selection,proper time and energy-momentum invariants are checked.
  • Quantum state normalization,phase,boundary and probability-current measures remain distinct.
  • Atomic/solid-state/nuclear counts,occupations,energy and rate accounts close under declared models.
  • Independent standards,fitted inputs and genuinely unused records remain separate.
  • Original-reading bounds and unresolved calibration/mechanism alternatives are retained.
  • First report,actual critique,substantive revision and a newly frozen assignment/response are preserved.
  • Synthetic content,public keys and test fixtures are not substituted for real learner mastery,supervised practical records or institutional credit.

Retain raw-data identifiers, provenance, units, prior predictions, methods, calculations, competing explanations and safety boundaries. State explicitly when data are simulated, supplied or genuinely observed. This saved text cannot verify a real experiment; do not invent measurements or completed supervised work. Maximum 12,000 characters; retain larger evidence files separately and cite them.

A nonempty report is only a saved submission. First and revised reports remain separate and cannot be overwritten. A critique of the first report is required before retaining one revision.

Fresh transfer direction

Require a reviewer-frozen new packet with all six category claims,changed numerical and conceptual premises,at least one shared-calibration alternative and one unused prediction. Keep first reasoning before feedback;retain resources,assistance and prior exposure. Actual practical and institutional-credit gates remain external.

A human must supply the actual new task, evidence and conditions before the learner responds. The transfer-direction text is not itself an unseen assessment. Use the retained assignment form after the first project; exposed public task identifier: expanded-public:university-physics3.

Science backups preserve each course's separate responses, exposure, rubric reviews and project history. Older backups do not reset attempts or erase known exposure. Divergent same-version immutable responses and incompatible same-version project histories are rejected rather than silently replaced; preserve both files for review.

Sources and boundaries
  • All 59 finite-plan destinations are authored; independent final scientific/source-action review passed. This is not every textbook section, advanced quantum training or an institutional credit claim.
  • All category records and constitutive models are supplied or generated. No actual gas handling, heating, pressure-vessel, optical-source, nuclear-material or detector operation is requested or claimed.
  • Authored lessons, model tests and public feedback do not establish independent learner mastery, institutional credit or real laboratory completion.
  • Actual browser/mobile/keyboard observations and qualified external evaluation remain separate from compile and numerical checks.
  • The fixed SC09 scope and exact category actions are recorded in the authoring plan; counts are a finite authoring contract, not a universal textbook or accreditation requirement.

Original LearnAI explanations and tasks use the references for scientific scope. Any attributed dataset or image has its own declared provenance. Laboratory or field activity requires an appropriate educator-approved protocol; no hazardous real-world operation is required by the guided path.

Save a science backup or import one

Science work is stored locally in this browser, separately from mathematics and AI. It does not sync automatically. Use this science-only backup; this checkout's older all-subject export does not include science.

A legacy file is available only when the complete snapshot fits the 36 MB limit. For larger snapshots, prepare a complete file set below; never discard notebooks to make a smaller file.

Matching imported notebook drafts replace their current drafts. Omitted lessons and known first attempts remain. Export your current work first if you want to retain both drafts.

Complete file sets and course backups

A file set can hold more work than one science file. Keep its manifest and every part together. Each file is limited to 36 MB. This format needs this version of LearnAI or a compatible newer version; older versions can use only the legacy single-file backup above.

The set includes every saved science course and global continuation at this moment. Later edits need a new export. A conflicting tab exports its own visible work, which may differ from saved work in another tab.

0 file(s) selected. File order and filenames do not determine identity. Missing, changed or conflicting parts block the entire restore; no good part is applied by itself.

Science storage: loading. No account or remote computation is required.