1. Circular Motion AP PHYSICS 2

2. Uniform Circular Motion

3. Example 1 The Moon’s nearly circular orbit about the earth has a radius of about 384,000 km and a period T of 27.3 days. Determine the acceleration of the Moon toward the earth.

4. Example 2 A 0.150 kg ball on the end of a 1.10 m-long cord is swung in a vertical circle. A) Determine the minimum speed the ball must have at the top of its arc so that it continues moving in a circle. B) Calculate the tension in the cord at the bottom of the arc assuming the ball is moving at twice the speed of part A. What is the minimum tension on the cord at the top of the swing if it is to continue swinging?

5. Example 2 cont’d B) Calculate the tension in the cord at the bottom of the arc assuming the ball is moving at twice the speed of part A.

6. Newton’s Law of Universal Gravitation

7. Example 3

8. Example 4 A geosynchronous satellite is one that stays above the same point on the equator of the Earth. Such satellites are used for such purposes as cable TV transmission, for weather forecasting, and as communications relays. Determine a) the height above the Earth’s surface such a satellite must orbit and b) such a satellite’s speed. What forces are acting on the satellite? Since it is geosynchronous it orbits once every 24 hours, thus:

9. Example 4 cont’d

10. Homework! Chapter 5: Questions 1, 9 Problems 7, 25, 29, 39