1. As the automobile in Figure 33 is being lifted, how does the change in oil level in the reservoir compare to the distance the automobile moves?
2. If a friend commented that a hydraulic device is a common way of multiplying energy, what would you say?
1. The car moves up a greater distance than the oil level drops, since the area of the piston is smaller than the surface area of the oil in the reservoir.
2. No, no, no! Although a hydraulic device, like a mechanical lever, can multiply force, it always does so at the expense of distance. Energy is the product of force and distance. Increase one, decrease the other. No device has ever been found that can multiply energy!