# Pressure and Density.

• LongFTW

## Homework Statement

Q1.A cylinder of length 10cm and radius 4cm has its axis vertical and its top end 15cm below the surface of a large beaker of water.
Calculate:
a) the pressure on the upper and on the lower ends of the cylinder due to the water
b) the force on the upper and on the lower ends of the cylinder due to the water
c) hence state the loss in weigh of the cylinder when immersed in water.

Q2.A solid metal cube, each side 3cm long has a mass of 207.8grams.
Calculate:
a) the density of the metal kg m^-3
b)the apparent mass of the cube when immersed in a liquid of density 850kg m^-3

I am completely stumped about these 2 questions and have no idea how to obtain the formula. So if anyone can just post the formula for me would be great.

## The Attempt at a Solution

Welcome to PF!

Hi LongFTW! Welcome to PF! Pressure at depth h is ρgh, where ρ is density (of water).

That should enable you to do Q1 …

show us how far you get, and where you're stuck, and then we'll know how to help! Never mind, I figured it out with some notes in my book, thanks for the help anyways.