Question

A 50 kg girl wearing high heel shoes balances on a single heel. The heel is circular with a diameter 1.0 cm. What is the pressure exerted by the heel on the horizontal floor ?

Answer 1

Mass of the girl, m = 50 kg
Diameter of the heel, d = 1 cm = 0.01 m
Radius of the heel,$r = \frac{d }{ 2}$ = 0.005 m
Area of the heel = πr2

= π(0.005)2

= 7.85 × 10–5 m2
Force exerted by the heel on the floor :

F = mg

= 50 × 9.8

= 490 N
Pressure exerted by the heel on the floor :

$P = \frac{Force }{ Area }$

$= \frac{490 }{7.85 × 10 ^{- 5}}$

= 6.24 × 10 6 N m - 2
Therefore, the pressure exerted by the heel on the horizontal floor is 6.24 × 10 6 N m-2.