PLEASE HELP!! A 2.0 kg moving cart hits a spring with a spring constant 50.0 N/m. Assume the system is frictionless. When the cart has come to rest, how far has the spring compressed?

Aball tossed vertically upward from the ground next to a building passes the bottom of a window 1.8 s after being tossed and passes the top of the window 0.20 s later. the window is 2.0 m high from top to bottom. what was the ball's initial velocity? the unit vector j^ is directed upward. how far is the bottom of the window from the launch position? how high does the ball rise above the launch position?

What are two different ways you could find the value of a? explain these methods.

Ryan is examining the energy of the particles in a bar of gold. what is ryan most likely studying?