# Two trucks are unloading 100 forty pound boxes of nails to a pallet 4 feet below the truck bed. The worker on one of the trucks has the use of a hand truck and a ramp. The worker on the other truck is lifting the 100 forty pound boxes with no ramp and no hand truck. Ignoring the effect of friction, the worker with the ramp and hand truck is

doing the same amount of work as the worker on the other truck.

Explanation

It is true that work is measured in joules but this answer is misleading. Work is defined as force x distance so 100 joules of work would be wrong. The correct answer is "3" because the distance moved and the force applied are the same regardless of whether a ramp and hand truck are used. The vertical distance of 4 feet is the same. The amount of force needed to move the 40 pound boxes is the same whether the force is applied straight up and down or on a ramp. The ramp may make the task easier for the worker to accomplish, but it does not change the amount of work to be accomplished.