In a car left, compressed air exerts a force on a piston with a radius 5.0 cm this pressure is transmitted to a second piston with a radius of 15.0 cm. How large a force must the compressed air exert to lift a 1.33 x 10^4 N car?

Arailroad car collides with and sticks to an identical railroad car that is initially at rest. after the collision, the total kinetic energy of the two cars is a) the same as before. b) half as much as before. c) one third as much as before. d) one fourth as much as before. e) twice as much as before.