- #1

Abu

## Homework Statement

The large cylinder in a hydraulic press has 3 times the surface area of the small cylinder. What force should be applied to the small cylinder to create a lifting force of 7200 Newtons

In a hydraulic-brake system, a force of 25 N can be applied to a surface area of 5 cm^2. What force can thus be exerted on each brake cylinder having an area of 100 cm^2

I have completed these problems but I am unsure if my work makes sense or if it is correct.

## Homework Equations

P = F/A

## The Attempt at a Solution

For the first problem, I identified the lifting force, 7200, as P (pressure). I thought that if the large cylinder is 3A (A is surface area), then that means

7200 = F/3A And since surface area is inversely proportional to the pressure, then the force is:

7200/3 = 2400 N

For the second problem, I applied the same formula to first answer for the pressure of the preliminary set of information I am given:

P = F/A

P = 25/5

P = 5

Then I used 500 again to find the force applied for the 100cm^2 cylinder

5 = F/A

5 = F/100

F = 500 Newtons

Are these solutions correct? I am unsure about the units I should be using also, because to me my answer for the second question seems wrong. But that was the only way that made sense to me.

Thanks.