Week 10 (Mar. 18 - 22)

Read: Mass, Momentum and Force (Chap. 19); and Absolute and Relative Motion (ASGv2 Chap. 20).

Key topics: Mass, momentum, inertia, force, centripetal force, absolute and relative motion.

PHY 201 Lecture: Coordinate transformations and their application to absolute and relative motion.
Quiz: No quiz on Monday since spring break was last week.


  1. Inertia and Force (Ex. 19.1),
  2. Centripetal Force (Ex. 19.2);
  3. Relative linear motion (Ex. 20.1)
  4. PHY 201: Absolute rotational motion (Ex. 20.2)

Lab: Force diagram lab. Sample force table picture. Logger Pro analysis screenshot.

Chapter 19: Let's start with some biographical comments on Isaac Newton.

To understand the American revolution of 1776, one must understand what they were rebelling against: the British monarchy. Similarly, to understand the scientific revolution, one must understand what they were rebelling against: the scientific philosophy of Aristotle and his medieval followers. In the next four lecture videos, I provide an overview of the traditional Aristotelian/Medieval philosophy of science. This will help you understand the context in which Newton was doing his work.

Newton's Principia begins with some definitions. The next few videos discuss Newton's definitions of "mass", "inertia", "momentum", and "force".

Chapter 20: In his "Scholium" at the end of his definition, Newton steps back and considers what one means by terms such as "space" and "time" and "motion". In particular, he considers whether all measurements of these quantities are relative, or whether there is a such thing as absolute space, absolute time, and absolute motion? This may seem a bit abstract, but it is extremely important, since Einstein's 20th century book Relativity was largely a reaction to (and rejection of) Newton's views on space, time and motion.

Physics 1