1. Monday 6/8 PHYS 2010 Nathalie Hoffmann University of Utah

2. Uniform Circular Motion An object on a circular path accelerates even if its speed is constant.

3. Centripetal acceleration

4. Practice Problems A ball spins on a 0.870-m-long string with a constant speed of 3.36 m/s. Calculate the acceleration of the ball. Be sure to specify the direction of the acceleration. The space shuttle is in orbit about 300 km above the surface of Earth. The period of the orbit is about 5.43 × 10 3 s. What is the acceleration of the shuttle? (The radius of Earth is 6.38 × 10 6 m.) Modern pilots can survive radial accelerations up to 9g (88 m/s 2 ). Can a fighter pilot flying at a constant speed of 500 m/s and in a circle that has a diameter of 8800 m survive to tell about his experience?

5. Answers P1.1: 13.0 m/s toward the center of the circle P1.2: 8.94 m/s toward the center of Earth P1.3: Yes. a = 5.80g