Physics 1: Mechanics

Proof required

Link the public repo with the odd-numbered problems of chapters 4–6 and the 8.01SC problem sets for weeks 1–4 written up (a typeset PDF, LaTeX source or notebook), and show the self-check: which answers matched and how you fixed the ones that did not.

What gets checked

• Each force problem starts from a labelled free-body diagram.
• Units and signs are right in every answer.
• Answers that disagreed with the key are reworked, with the mistake named.

Common mistakes

• Answers copied from the key with no working.
• Wrong units or missing signs.

Powstik Guide

A public write-up of the odd-numbered problems of chapters 4–6 and the 8.01SC problem sets for weeks 1–4, with the self-check shown.

Steps

1. Study the linked course and chapters.
2. Solve the problems on your own first.
3. Check them against the self-check and rework the misses.
4. Typeset the write-up (LaTeX or a notebook) in a public repo.
5. Ask someone who knows physics to check it.

README
Physics 1: Mechanics, unit 1: Motion and Newton's laws
Problems:
Self-check result (matched / reworked):
What I got wrong first and why:

What gets sent back

• No working shown.
• The self-check result is missing.

Resources

What a verifier looks for

• Each force problem starts from a labelled free-body diagram.
• Units and signs are right in every answer.
• Answers that disagreed with the key are reworked, with the mistake named.
• Is the physics right, not just the final number?

You'll sign in first, then come straight back here.

Proof required

Link the public repo with the odd-numbered problems of chapters 7–9 and the 8.01SC problem sets for weeks 5–8 written up (a typeset PDF, LaTeX source or notebook), and show the self-check: which answers matched and how you fixed the ones that did not.

What gets checked

• Each problem names its principle (work–energy theorem or a conservation law) and why it applies.
• Collisions state whether kinetic energy is conserved.
• Answers are checked against the key, and misses are reworked.

Common mistakes

• Answers copied from the key with no working.
• Wrong units or missing signs.

Powstik Guide

A public write-up of the odd-numbered problems of chapters 7–9 and the 8.01SC problem sets for weeks 5–8, with the self-check shown.

Steps

1. Study the linked course and chapters.
2. Solve the problems on your own first.
3. Check them against the self-check and rework the misses.
4. Typeset the write-up (LaTeX or a notebook) in a public repo.
5. Ask someone who knows physics to check it.

README
Physics 1: Mechanics, unit 2: Energy and momentum
Problems:
Self-check result (matched / reworked):
What I got wrong first and why:

What gets sent back

• No working shown.
• The self-check result is missing.

Resources

What a verifier looks for

• Each problem names its principle (work–energy theorem or a conservation law) and why it applies.
• Collisions state whether kinetic energy is conserved.
• Answers are checked against the key, and misses are reworked.
• Is the physics right, not just the final number?

You'll sign in first, then come straight back here.

Proof required

Link the public repo with the 8.01SC problem sets for weeks 9–14, then the Saylor PHYS101 final exam written up (a typeset PDF, LaTeX source or notebook), and show the self-check: which answers matched and how you fixed the ones that did not.

What gets checked

• Torque and angular momentum are used with the right axis.
• Orbits use energy and angular momentum correctly.
• The Saylor final score is shown.

Common mistakes

• Answers copied from the key with no working.
• Wrong units or missing signs.

Powstik Guide

A public write-up of the 8.01SC problem sets for weeks 9–14, then the Saylor PHYS101 final exam, with the self-check shown.

Steps

1. Study the linked course and chapters.
2. Solve the problems on your own first.
3. Check them against the self-check and rework the misses.
4. Typeset the write-up (LaTeX or a notebook) in a public repo.
5. Ask someone who knows physics to check it.

README
Physics 1: Mechanics, unit 3: Rotation and gravity
Problems:
Self-check result (matched / reworked):
What I got wrong first and why:

What gets sent back

• No working shown.
• The self-check result is missing.

Resources

What a verifier looks for

• Torque and angular momentum are used with the right axis.
• Orbits use energy and angular momentum correctly.
• The Saylor final score is shown.
• Is the physics right, not just the final number?

You'll sign in first, then come straight back here.

Proof required

Link the public repo with the method, raw measurements, a photo of the set-up (and the laser's class label, if one is used), the analysis and the result, the result with its uncertainty, and a README that says what you did and what limits the result.

What gets checked

• g and its uncertainty come from the fit, with the scatter of the repeats as error bars.
• Small swings are used, a big swing is tested, and g is compared with the local value (about 9.81 m/s²).
• The set-up is safe: no mains power, no laser above class 2, reflections kept away from eyes, no radioactive material, no harmful heat or pressure.

Common mistakes

• A result with no uncertainty.
• Code or data that cannot be rerun from the repo.

Powstik Guide

A measurement of the acceleration due to gravity with a home pendulum (a weight on a string), timed with a phone, in a public repo.

Steps

1. Write down what you expect before you start.
2. Time 20 swings at five or more string lengths, repeat each three times, and fit period squared against length with a straight line; g = 4π²/slope, and the intercept absorbs any error in where the length is measured to.
3. Work out the uncertainty from your own data.
4. Compare with the accepted value and explain any gap.
5. Write the README and ask someone who knows physics to check it.

README
Physics 1: Mechanics — Measure g with a pendulum
What I expected:
Method:
Result (value ± uncertainty):
Accepted value and comparison:
What limits the result:

What gets sent back

• No uncertainty, or one that is guessed.
• An unsafe set-up.

Resources

What a verifier looks for

• g and its uncertainty come from the fit, with the scatter of the repeats as error bars.
• Small swings are used, a big swing is tested, and g is compared with the local value (about 9.81 m/s²).
• The set-up is safe: no mains power, no laser above class 2, reflections kept away from eyes, no radioactive material, no harmful heat or pressure.
• The uncertainty is worked out from the data or runs (spread of repeats, instrument limits, fit errors or a range of inputs), not guessed, and it is shown on the result.
• Is the physics right, and could someone rerun it from the repo?

You'll sign in first, then come straight back here.