A closed cubical chamber resting on the floor contains oil and a piston.If you push down on the piston hard enough to increase the pressure just below the piston by an amount Δp,which of the following statements is correct? (There could be more than one correct choice. )
A)The pressure everywhere in the oil will increase by Δp.
B)The pressure at the bottom of the oil will increase by more than Δp.
C)The pressure at the top of the oil will increase by less than Δp.
D)The pressure on the sides of the chamber will not increase.
E)The increase in the force on the top of the chamber will be the same as the increase in the force on the bottom of the chamber.

Question

Quizplus · Accepted Answer

The pressure in a fluid in a closed container is transmitted undiminished in all directions (Pascal's principle), so if the pressure just below the piston increases by Δp, the pressure everywhere in the oil will also increase by Δp, making choice A correct. Since the pressure increase is uniform throughout the oil, the force exerted by the oil on any surface in contact with it, including the top and bottom of the chamber, will increase equally if the areas are the same, making choice E correct as well.

A Closed Cubical Chamber Resting on the Floor Contains Oil