OCR MEI
Further Mechanics Minor
2024
June
Q2
8 marks
Moderate -0.5
2
- State the dimensions of force.
Use the following metric-imperial conversion factors for the rest of this question.
A unit of force used in the imperial system is the pound-force (lbf). 1 lbf is defined as the gravitational force exerted on 1 lb on the surface of the Earth.
- Show that 1 lbf is approximately equal to 4.45 N .
The pascal (Pa) is a unit of pressure equivalent to 1 Newton per square metre. Pressure can also be measured in pound-force per square inch (psi).
A diver, at a depth of 40 m , experiences a typical pressure of \(5 \times 10 ^ { 5 } \mathrm {~Pa}\).
- Determine whether this is greater or less than the pressure in a bicycle tyre of 80 psi .
In various physical contexts, energy density is the amount of energy stored in a given region of space per unit volume.
- Show that energy density and pressure are dimensionally equivalent.