Finished Chapter 1 and want to go deeper — or stuck somewhere and need a second source? This is our curated list. Each entry has a short note on why it is useful and for whom.

Selection principle: Only freely accessible resources (videos, open textbooks, NIST/BIPM docs) — or standard reference books available in university libraries.

Video lectures

Walter Lewin — MIT 8.01: Classical Mechanics youtube.com/playlist?list=PLyQSN7X0ro203puVhQsmCj9qhlFQ-As8e Legendary course. Lect 1 (measurement, dimensional analysis, estimation) and Lect 10 (pendulum + Hooke's law) map directly to our Chapter 1. Lewin is the master of live demonstrations — including hanging from a pendulum himself, which our pendulum experiment references.

Feynman Lectures — Vol I, Ch 5: Time and Distance feynmanlectures.caltech.edu/I_05.html Fermi estimation and dimensional analysis from a master of both. Full text free (Caltech). Chapter 1 (Atoms in Motion) is also useful for seeing physics from the bottom up.

3Blue1Brown — But what is a moment? youtube.com/watch?v=fBadC_5DdRw Grant Sanderson's math-focused animations — good visual introduction to big/small numbers and estimation.

Veritasium — How to Weigh a Kilogram Using the Kibble Balance youtube.com/watch?v=Oo0jm1PPRuo Companion to §1.5 — Derek Muller takes a full tour of NIST and the Kibble balance.

Open textbooks

OpenStax University Physics Vol 1 openstax.org/books/university-physics-volume-1

Halliday, Resnick, Krane — Physics (Volume 1) The primary reference for this chapter. If you have access, check the Sample Problems and Problems at the end of Chapter 1 — different scenarios exercising the same recipes.

Feynman Lectures on Physics — Vol I feynmanlectures.caltech.edu/ Volume 1 is free online. For Chapter 1, read: Chapter 1 (Atoms in Motion), Chapter 5 (Time and Distance), Chapter 22 (Algebra).

Metrology (standards and measurement)

NIST — Guide for the Use of the International System of Units (SP 811) physics.nist.gov/cuu/pdf/sp811.pdf The official NIST SI guide — with complete conversion tables, notation rules, and the constants list. The final reference for debugging tricky conversions.

BIPM — SI Brochure (9th Edition) bipm.org/en/publications/si-brochure The official SI document — precise definitions of the 7 base units (post-2019 redefinition), conversion appendices, and history of each unit. If you're unsure about any value, this is the ultimate reference.

CODATA — Recommended Values of the Fundamental Physical Constants physics.nist.gov/cuu/Constants/ Precise values of physical constants — speed of light, Planck's constant, Avogadro, Boltzmann, ... with the latest precision. For any serious calculation, refer to this rather than memorizing.

NIST Standard Reference Database — Physical Constants nist.gov/pml/fundamental-physical-constants The official constants table with uncertainties — useful for reporting a final number with correct sig figs.

Interactive / simulations

PhET Interactive Simulations — Estimation phet.colorado.edu/en/simulations/estimation Visual practice of length, area, and volume estimation. For sharpening size intuition.

Powers of Ten (classic) youtube.com/watch?v=0fKBhvDjuy0 Charles and Ray Eames's classic 1977 short — from 10^24 m down to 10^{-16} m in factor-of-10 steps. The best way to feel astronomical/quantum scales.

Our interactive experiments

All three inject random error in the background and include a "Python analysis" section (in-browser Pyodide).

Review articles (advanced)

Redefining the SI (2019) bipm.org/en/measurement-units/rev-si/ The 2019 SI redefinition, which moved the kilogram from the IPK to Planck's constant. A milestone in the history of measurement.

Time and Time-keeping — SP 250-25 nist.gov/pml/time-and-frequency-division If you want more about cesium atomic clocks (our Chapter 1 appendix), NIST-F1/F2 and the optical clock program are documented here.

A few notes on using these resources

  1. Always convert to SI before computing. Even if a book or website works in other units (imperial, cgs), in your own calculations stick to SI.

  2. The primary reference is BIPM/NIST, not Wikipedia. For precise constants, always refer to CODATA. Wikipedia probably cites CODATA, but for formal reporting quote the primary source.

  3. Use Feynman for intuition, Halliday/OpenStax for recipes, NIST for precise values. Each source has its own style — the best approach is to combine them.

  4. In code, use standard libraries. scipy.constants has all CODATA constants. pint in Python, Units.jl in Julia, units in Rust — all handle factor-label conversions and catch unit-mismatch errors for you.

End of Chapter 1

This is the end of Chapter 1 (Measurement). The tools you learned:

Next chapter: Motion Along a Straight Line (1D kinematics) — applying these tools to real mechanics problems.

📚 Feedback: if you know another good resource that's missing here, let us know so we can add it. This list is continuously updated.

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