# Pascal's Principle

## Pressure is transmitted undiminished in an enclosed static fluid.

Any externally applied pressure is transmitted to all parts of the enclosed fluid, making possible a large multiplication of force (hydraulic press principle). The pressure at the bottom of the jug is equal to the externally applied pressure on the top of the fluid plus the static fluid pressure from the weight of the liquid.

### How to drop the bottom out of a bottle

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# Hydraulic Press

A multiplication of force can be achieved by the application of fluid pressure according to Pascal's principle, which for the two pistons implies

This allows the lifting of a heavy load with a small force, as in an auto hydraulic lift, but of course there can be no multiplication of work, so in an ideal case with no frictional loss:

## Calculation

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# Hydraulic Press Calculation

 Example of hydraulic press action. For piston radii: = cm =in = cm =in the cylinder areas are = m^2 = m^2 and the force multiplication is = For an input force = N = lb, Pascal's principle gaurantees that = kPa = lb/in^2.
Applying this pressure to the output cylinder yields the lifting force:
= N = lb,
A price must be paid for an increased lifting force, since conservation of energy must be satisfied. For an ideal hydraulic press, the work must satisfy , so that to lift the load a distance of
= m = ft, the input piston must be moved a distance
= m = ft,
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# Automobile Hydraulic Lift

Force multiplied by hydraulic press, based on Pascal's principle. The fluid in the small cylinder must be moved much further than the distance the car is lifted.

## Calculation

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