The hydraulic lift is able to lift large weights with a small input of force. A small pump can lift a car weighing thousands of pounds. Pascal's principle states that an increase in pressure in a fluid is felt throughout the fluid. In the hydraulic lift the pressure applied to the narrow piston is equal to the pressure increase on the larger piston. We can calculate the force exerted by the large piston in terms of the force on the narrow piston. The subscript I refers to the small piston and the subscript O refers to the large piston. The force on the small piston is multiplied by the large ratio of the areas of the two pistons to obtain the force on the large piston. The narrow piston must be moved down a large distance to move the larger piston up a small distance. The volume of fluid displaced by the narrow piston equals that pushing the large piston up. Suppose that the area of the small piston is 50 square centimeters and it is pushed down with a force of 50 Newtons on it. How much force is being exerted upward by the large piston with an area of 2.0 square meters? What's the pressure at 35 meters depth of water for average conditions? Do not neglect atmospheric pressure.

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