How much work would it take to overcome the friction if the mass of the box was 5 kg, and an applied force of 20 Newtons caused the box to move 25 meters until it reached a final velocity of 10 m/s?

Alfred pushes on a heavy box, but cannot move it. the box has a lot of inertia motion friction gravity

Two masses are connected by a rope that hangs over a pulley as shown below. the pulley is a uniform cylinder of radius 푅=0.381meters and mass 푀=3.1푘푔. initially 푚"is on the ground and 푚#rests 2.5 meters above the ground. if the system is released, use conservation of energy to determine the speed of 푚#just before it strikes the ground. assume the pulley bearing is frictionless.

Vi. on another planet, a spring with constant 4.7 n/m is set up and allowed to expand verticaly freely. 8.4kg mass is placed on the spring and the spring extends 5.28m. calculate the exected extension on earth.