"AP Physics C" Problems

Pre-College Issues High School Life
1

<p>If you could answer these questions showing work that would be great.</p>

<p>27.) A 91 kg man lying on the surface of negligible friction shoves a 68 g stone away from him, giving it a speed of 4.0m/s. What is the initial velocity of the other block?</p>

<p>29.) A 75 kg man is riding on a 39 kg cart traveling at a speed of 2.3m/s. He jumps off with zero horizontal speed relative to the ground. What is the resulting change in the speed of the cart?</p>

<p>Thanks.</p>

2

<p>all it is is conservation of momentum.</p>

<p>just make it all add up to a constant.</p>

3

<p>27.) m1<em>v1 = m2</em>v2
v1 = 68*4/91000 = 0.003 m/s = 3 mm/s</p>

<p>29.) (m1+m2)<em>vi = m2</em>vf
vf = (75+39)*2.3/39 = 6.72 m/s
change in speed = vf - vi = 6.72 - 2.3 = 4.4 m/s</p>