Hydraulics

Question 1

What is the key property of liquids?

Answer 1

They are virtually incompressible

Question 2

What does virtually incompressible mean?

Answer 2

You can’t squash them

Their volumes and densities stay the same

Question 3

What can you do as a result of liquids being incompressible and able to flow?

Answer 3

Apply a force at one point in the liquid and it will be transmitted to other points in the liquid

Question 4

What does the balloon with holes in example show?

Answer 4

Thé force applied to water at the top of the balloon is transmitted to the water in other parts of the balloon

Pressure can be transmitted throughout a liquid

Question 5

Hoe is pressure in a liquid transmitted?

Answer 5

Pressure in a liquid is transmitted equally in all directions

Question 6

What is pressure measured in?

Answer 6

Pa

Pascals

Question 7

How do you work out pressure?

Answer 7

Force / cross sectional area

Question 8

What are hydraulics systems used as?

Answer 8

Force multipliers- they use a small force to produce a bigger force using liquid and cross sectional area

Question 9

What does a simple hydraulics system usually have?

Answer 9

Two pistons
One with a smaller cross sectional area than the other but as pressure is transmitted equally through a liquid the pressure at both pistons is the same

Question 10

Explain how a hydraulics system works?

Answer 10

1st piston a pressure is exerted on the liquids using a small force over a small area
This pressure is transmitted to the second piston
The second piston has a larger area so there will be a larger force

Question 11

What are hydraulics systems used in?

Answer 11

Car braking systems
Hydraulic car jacks
Deployment of landing gear on some aircraft