Pressure, Force and Area

Use pressure = force ÷ area.

So $1000\text{ N}÷0.5{\text{ m}}^2=2000{\text{ N/m}}^2$.

The pressure is 2000 N/m².

Use force = pressure × area.

So $900{\text{ N/m}}^2\times 2{\text{ m}}^2=1800\text{ N}$.

The force is 1800 N.

Use area = force ÷ pressure.

So $1800\text{ N}÷1200{\text{ N/m}}^2=1.5{\text{ m}}^2$.

The area is 1.5 m².

(To find area you divide the force by the pressure. Dividing the other way round, $1200÷1800$, gives a wrong, much smaller answer.)

First find the area of the base: for a rectangle, area = length × width $=1.5\text{ m}\times 0.6\text{ m}=0.9{\text{ m}}^2$.

Then use pressure = force ÷ area. So $1350\text{ N}÷0.9{\text{ m}}^2=1500{\text{ N/m}}^2$.

The pressure is 1500 N/m².

First find the area of the slab: for a square, area = side × side $=0.5\text{ m}\times 0.5\text{ m}=0.25{\text{ m}}^2$.

Then use force = pressure × area. So $2000{\text{ N/m}}^2\times 0.25{\text{ m}}^2=500\text{ N}$.

The force is 500 N.

First find the area of the base using area = force ÷ pressure. So $800\text{ N}÷3200{\text{ N/m}}^2=0.25{\text{ m}}^2$.

For a square base, area = side × side, so the side length is the square root of the area: $\sqrt{0.25{\text{ m}}^2}=0.5\text{ m}$.

The side length is 0.5 m.

(A common mistake is to stop at the area, 0.25 m², and forget to take the square root to get the side.)