Question

A girl is wearing a pair of flat shoes. She weighs 550 N. The area of contract of one shoe with the ground is 160 cm². What pressure will be exerted by the girl on the ground.
(a) if she stands on two feet?
(b) if she stands on one foot?

Answer 1

Area of one foot = 160 cm² (160/10,000 = 0.016 m²)
Area of two feet = 0.016 × 2 = 0.032m²
Pressure = ?
Weight = 550 N
$$\begin{gathered} \mathrm{Pressure}=\frac{\mathrm{Force}}{\mathrm{Area}} \\ =\frac{550}{0.032} \end{gathered}$$
Pressure = 17,187.5 Pa or N/m²
Ans: Pressure = 17,187.5 Pa or N/m².

(b)
Area = 160 cm² (160/10,000 = 0.016 cm²)
Pressure = ?
Weight = 550 N
$$\begin{gathered} \mathrm{Pressure}=\frac{\mathrm{Force}}{\mathrm{Area}} \\ =\frac{550}{0.016} \end{gathered}$$

Pressure = 34,375 Pa
Answer: Pressure = 34,375 Pa or N/m².