Question

A girl is wearing a pair of flat shoes. She weighs 550 N. The area of contact of one shoe with the ground is $160c{m}^2$. 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

F = mg = 550 N

Area when she stands in two feet=$a_1=2\ast 160c{m}^2=320c{m}^2=0.32m^2$

Area when she stands in one foot=$a_2=160c{m}^2=0.16m^2$

(a) $Pressure,P_1=\frac{F}{a_1}=\frac{550}{0.32}=1718.75Pa$

(b) $Pressure,P_2=\frac{F}{a_2}=\frac{550}{0.16}=3437.5Pa$