PHYSICS · Multi-part · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
State whether the work done is positive, negative or zero in each of the following cases:
(i) A girl pushes a shopping cart straight ahead along a horizontal floor.
(ii) The force of friction acts on a box sliding to the right on a rough surface.
(iii) The gravitational force acts on a satellite moving in a perfectly circular orbit around Earth.