How do you find the density of an unknown liquid

Which example has gravitational potential energy? a. a horse slowing down from a run b. an apple about to fall from a tree branch c. a bicycle being pedaled down a horizontal path d. beaker sitting on the floor

All the simple machines make work easier to do by changing the or of a force. a. size; type b. work; type c. size; direction d. type; direction

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