A mass of 12 kg is sliding along a frictionless surface at a speed of 5 m/s.
It collides perfectly inelastically with a stationary mass of 24 kg which is attached to
a spring. If the spring constant is 225 N/m, where are the stuck-together masses 3
seconds after the collision?
I know momentum before collision is 12*5= 60
But I don’t know what to do from here … I know momentum has to be conserved but not energy but I am having trouble understanding what can the next step be.
I hope someone can help me.