Chapter 5- Pressure

Question 1

Pressure SI units

Answer 1

1 pascal= 1N/m2

Question 2

Define hydrostatic pressure

Answer 2

Hydrostatic pressure is defined as the liquid pressure at the bottom of a liquid column due to the liquid above. Given by height x liquid density x gravitational acceleration

Question 3

Why do hydraulic systems work; state Pascal’s law

Answer 3

Hydraulic systems work because liquids are almost incompressible and they transmit pressure equally in all directions (Pascal’s Law)

Question 4

Define atmospheric pressure

Answer 4

Atmospheric pressure is due to the force per unit area exerted against a surface by the weight of the air above that surface. Atmospheric pressure acts in all directions and all surfaces exposed to the atmosphere experience atmospheric pressure

Question 5

What is excess pressure?

Answer 5

Excess pressure is the difference between gas pressure and atmospheric pressure

Question 6

State Boyle’s Law

Answer 6

Boyle’s law states that for a fixed mass of gas at constant temperature, volume V of the gas is inversely proportional to pressure the pressure P

P1V1=P2V2

Question 7

Define pressure

Answer 7

Pressure is defined as the force acting normally per unit area

P= f/a