A worker lifts a box on the roof of a building 15m high at a constant speed If the work of the force exerted by the worker is 300J, find the weight and mass of the box.

Why do astronauts in the space shuttle weigh less?

Two carts, one of mass 2m and one of mass m, approach each other with the same speed, v. when the carts collide, they hook together. assume that positive momentum is to the right. which graph best represents the momentum of both carts over time, before and after the collision?

Which describes increasing the efficiency of energy resource