A dog is pulling a sled by applying a force of 75 newtons on it. The angle of force from the ground is 45°. If the sled moves 15 meters, how much work is done by the dog on the sled?

Work done = force x distance (where the force is in the direction of the distance travelled)

We must resolve the force so that it is horizontal to the ground

force = 75cos45

Then simply plug into the formula, so:

work done = 75cos45 x 15 = 795.49 ... Nm = 795 Nm (3 sig. fig.)