Step by step
The question
Question: find the pressure when the force is 75 N and the area is 0.5 m².
Force 75 N, area 0.5 m². Find the pressure.
1 Write the rule
The rule: pressure is the force divided by the area.
pressure = forcearea
Pressure tells us how much force pushes on 1 m².
So its unit is N per m².
pressure = the force on 1 m²
unit: N ÷ m² → N/m²
2 Put the numbers in
The force is 75.
The area is 0.5.
p = 750.5
3 Work it out
Careful!
The force goes on the top.
The unit, N/m², shows it: N on the top.
Careful: not 0.575 ✗
75 divided by 0.5 is 150.
pressure = 150 N/m²
To divide by 0.5, we move the point in both numbers 1 place.
75 ÷ 0.5 = 750 ÷ 5 = 150
So the pressure is 150 N/m².
4 Check
Let's check.
150 in each m², for 0.5 m²: 150 times 0.5 is 75.
That is the force.
So the answer is right!
150 N in each m²: 150 × 0.5 = 75 N
Let's look back.
First: write the rule.
Then: put the numbers in.
Then: work it out.
Last: check.
Answer
75 ÷ 0.5 = 750 ÷ 5 = 150