P1D3 - pressure

Question 1

What is pressure + formula + unit

Answer 1

The force acting on each unit of surface area

Formula : force(N)/area(m^2 or cm^2) = pressure

Unit : n/m^2 = pascal (Pa) or n/cm^2

Question 2

State 2 uses of high pressure

Answer 2

1. injection devices such as syringes have small area to be able to apply high pressure and pierce skin, veins, etc
2. knives are very sharp and have a small area in order to exert high pressure and cut an object

Question 3

State 2 uses of low pressure

Answer 3

1. Snow shoes have a large area to distribute weight and prevent person from sinking
2. Wheels on a digger which have a large surface area and will therefore prevent the digger from sinking into the sand. Large tyre area = low pressure

Question 4

Pressure in a solid is..

Answer 4

weight/contact area

Question 5

When area increases, pressure

Answer 5

decreases