Forces & Pressure

Question 1

What is the equation for pressure?

Answer 1

Pressure = force / area

Question 2

What does pressure depend on?

Answer 2

Area the force is acting over and size of force

Question 3

What are the units for pressure?

Answer 3

Pascals (Pa)

Question 4

Why do gases exert pressure?

Answer 4

Their motion means they have collisions which causes pressure

Question 5

What does decreasing container size do to pressure?

Answer 5

Pressure increases because there’s less space so more collisions can happen

Question 6

What happens to atmospheric pressure as you go higher up?

Answer 6

It increases

Question 7

What does liquid pressure depend on?

Answer 7

Depth

Question 8

What is the equation for liquid pressure?

Answer 8

Pressure = height x density x gravitational field strength

Question 9

How do you investigate upthrust?

Answer 9

1. Use newton metre to weigh a metal object in the air
2. Repeat the test by weighing the same object when it’s completely in water
3. The newton metre reading should be less when in water
4. Difference between the two newton metre reading is equal to the upthrust on the object
5. Repeat test with the object partially immersed in water
6. This reading should be in between the previous readings

Question 10

When does an object float?

Answer 10

When it’s weight i’d equal to the upthrust

Question 11

When does an object sink?

Answer 11

When it’s weight is greater than the upthrust