Pressure and density

Question 1

Define pressure

Answer 1

The amount of force applied to an area
If a big force is applied to a small area you have high pressure
If a little force is applied to a large area you have low pressure

Question 2

Identify the units of measurement for pressure

Answer 2

Pascal (Pa) or N/m2

Question 3

Describe the formula triangle for pressure

Answer 3

Force = Pressure x area
Pressure = Force/ area
Area = Force/pressure

Always use N for force and m2 for area

Question 4

Explain how wearing snow shoes can help prevent someone sinking into the snow

Answer 4

Wearing snow shoes increases the area of the person coming into contact with the snow. Therefore this decreases the pressure acting downwards on the snow stopping them from sinking.

Question 5

Describe the formula triangle for density

Answer 5

Density = mass/volume

Question 6

identify the units for density

Answer 6

kg/m2
or
g/cm2

1g/cm2 = 1000 kg/m2

Question 7

Describe how you would calculate the density of an irregularly shaped object

Answer 7

1. Weigh the object on a mass balance to find its mass
2. Place the object into a measuring cylinder of water and record the change in volume ( this gives the volume of the object
3. Use the formula Density = mass/volume and you have the answer

Question 8

Describe how you would calculate the density of a liquid?

Answer 8

1. Find the mass of the container and the mass of the liquid in the container and subtract them to find the mass of the liquid.
2. Read the volume from a measuring cylinder
3. Use the formula Density = mass/volume and you have the answer

Question 9

What does the symbol for density look like

Answer 9

It is the Greek letter rho which looks like a curly p