a 4.0 kg box is released from rest on a frictionless ramp. The box slides from the ramp onto a rough surface with a friction coefficient .50. the box slides 2.0 m horizontally until it stops. what height was the box on the ramp ?

During cooling, the kinetic energy of the molecules falls. why does this happen? a. the motion of the molecules increases. b. the motion of the molecules slows down. c. the van der waals forces between molecules decrease d. the forces of attraction between the molecules are overcome.