A force is applied to a block on a frictionless inclined surface as shown in the diagram. What magnitude force is necessary to keep the block from sliding down the incline? The mass of the block is 69.7 kg and the angle of incline is 45.2 degrees. The magnitude of the force is _?

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.