# Worksheet: Relating Force, Pressure, and Area

In this worksheet, we will practice using the formula for pressure, p = F/A, to calculate pressures that are produced by forces acting on areas.

**Q7: **

A pressure of 400 Pa is applied to an
area of 2.5 m^{2}. What force applies this
pressure?

**Q8: **

A sofa with a mass of 125 kg
has a base with an area of
2.5 m^{2}. What pressure does
the sofa apply to the ground beneath it?

**Q9: **

A dancer with a mass of 50 kg is standing on the tips of the toes of one of her feet. She exerts a pressure of 490 kPa on the tips. What is the area, in square centimeters, of the part of the foot on which she stands?

**Q10: **

A press is used to crack rocks, applying a pressure of
750 kPa to a rock with a mass of
6.2 kg, as shown in the diagram. The
rock being crushed has a very uneven surface. The surface area in contact with the plates of
the press is 20 cm^{2}.

What is the average force applied to the rock by the press?

How many times heavier would the rock being crushed need to be for it to apply the same weight to the ground as the average force applied by the press? Round your answer to one decimal place.