Blocks A and B have masses m and 2m, respectively, and they are connected with the spring as shown. The spring is initially compressed and then the blocks are released. Which is the correct statement regarding the energy and momentum of the system?
A
B
If the surfaces are rough, only the momentum of the system is conserved
If the surfaces are rough, both the energy and momentum of the system are conserved
If the surfaces are smooth, both the energy and momentum of the system are conserved
If the surfaces are rough, only the energy of the system is conserved