P11: Pressure

Question 1

What is the equation for pressure?

Answer 1

Pressure = force/area

Question 2

What is the equation for the pressure of a liquid?

Answer 2

Pressure = height x density x gravitational field strength

Question 3

What are the units for density?

Answer 3

Kg/m^3

Question 4

Describe how upthrust occurs

Answer 4

When an object is submerged in liquid, it experiences a greater pressure on the bottom of the surface than on the top. This creates a resultant force upwards, which is upthrust.

Question 5

What happens to the atmosphere when altitude is increased?

Answer 5

It gets less dense

Question 6

What happens to the number of air molecules above a surface as the height of the surface above ground level increases?

Answer 6

The number decreases

Question 7

Describe the air when the height of a surface increases

Answer 7

There is less air above the surface than below it meaning, atmospheric pressure decreases as the height increases

Question 8

What determines the pressure of an object in liquid?

Answer 8

The weight of the water above the object, the density of the liquid and the gravitational field strength

Question 9

When would an object sink?

Answer 9

If it is more dense than the liquid

Question 10

When would an object float?

Answer 10

If it is less dense than the liquid