Homework Quiz #4 What about objects moving vertically…with or against gravity?

Ball Toss Sketch the distance-time graph and velocity-time graph for a ball that is tossed straight up in the air Graph from when the ball is released until it is caught

Ball Toss Analysis

Help students interpret graphs… Help students interpret graphs….parabola means same motion up and down as well as same time. Slope at peak would be zero so zero velocity at max height…zero velocity also shown on bottom graph and that the magnitude of g is constant since one slope.

Assuming no errors, what should the slope of the velocity/time graph be?

What would be the readings on a speedometer and odometer attached to the cliff diver after 1 second, 2 seconds, 3 seconds of fall?

Speedometer After 1 second of fall: vf = vi + at +10 m/s Known: vi = 0 and g = 10 m/s2 and time… After 1 second of fall: vf = vi + at vf = 0 + 10 m/s2 (1 s) = 10 m/s After 2 seconds of fall: vf = 0 + 10 m/s2 (2 s) = 20 m/s After 3 seconds of fall: vf = 0 + 10 m/s2 (3 s) = 30 m/s +10 m/s

Odometer After 1 second of fall: d = vit + ½ at2 Known: vi = 0 and g = 10 m/s2 and time… After 1 second of fall: d = vit + ½ at2 d = 0 + ½ (10 m/s2)(1s)2 d = 5 m After 2 seconds of fall: d = 0 + ½ (10 m/s2)(2 s)2 d = 20 m After 3 seconds of fall: d = 0 + ½ (10 m/s2)(3 s)2 d = 45 m

Which of the following statements is true about the diver’s velocity as he falls? His velocity is constant His velocity increases by the same amount each second His velocity increases by increasing amounts each second

Which of the following statements is true about the distance covered by the diver as he falls? The distance is constant for each second of fall. The distance increases by the same amount each second The distance increases by increasing amounts each second

The Ultimate Freefall Joe Kittinger August 16, 1960 (video - http://www.tinyurl.com/JKittinger) Joe Kittinger August 16, 1960 Jumped from 102,800 ft Fall lasted four minutes and thirty-six seconds, a record. Parachute opened at 17,500 ft Achieved maximum speed of 614 mph http://www.pbs.org/wgbh/nova/escape/skywave.html http://www.tinyurl.com/KittingerPBS

Felix Baumgartner New Free fall record 128,000ft Broke the sound barrier with only his body http://www.youtube.com/watch?v=iZp7DJb7CG0