Phy211 Spring 2009 Syracuse University Practice before Exam 3 Page 1
Physics 211, Spring 2009 Practice before Exam 3
1. Two carts of mass m1=3 kg and m2=5 kg are attached to each other. There is a compressed spring in
between them. The spring constant is k=3500 N/m. The carts are moving on frictionless track. Initially
they are moving with velocity of 1.5 m/s to the right. Then the carts are disconnected. They separate as the
spring is allowed to decompress. After the separation, velocity of the cart with mass m2 is 3.0 m/s to the
right.
1a. Find final velocity (magnitude and direction) of the cart with mass m1 after the separation.
1b. Find compression of the spring (∆x) before the cart separation (you will need to solve 1a first).
m1 m2
1.5 m/s
m2
m1
3.0 m/s
v1f = ?
before after
