Topic Objectives

Understand Galileo’s theory of motion and how it differed from that of Aristotle’s.
Understand Newton’s theory of motion and how it differed from that of Aristotle, and that of Galileo.
Understand Newton’s law of universal gravitation and how it was used to explain falling bodies and planetary revolution.
Understand terms velocity, acceleration, force, weight, mass, momentum.

Wednesday Reading Assignment

Trefil and Hazen, The Sciences, 3rd ed. Ch 2 pp. 36 to 49

Wednesday Active Learning Exercises

1)How could you use Newton's 1st law to explain to a friend why we don’t feel the Earth’s motion? Can you cite any examples that would support your explanation?

2) How would you distinguish between weight and mass? How could you use Newton's gravitational law to help explain the difference?

3) Estimate the acceleration due to gravity on the Moon using Newton’s Universal Law of gravitation. Using this, estimate your weight. What about on Jupiter?

Info: Mass_Jupiter=360 Earth masses, Radius_Jupiter=12 Earth radii

Mass_Moon= 1/80 Earth masses, Radius_Moon= ½ Earth radii

Reading for Friday

Excerpts from: Physics for the Inquiring Mind E. Rogers (1960).

http://web.sbu.edu/physics/faculty/dimattio/Clare102/physics.dimattio-sp03.htm

Questions for discussion:

1. How does Galileo's description of motion differ from that of Aristotle?

2. How does Newton's theory of motion compare to that of Galileo?

3. Why is Newton's theory of motion a good example of what a scientific theory should be?