Question

A 50 kg girl wearing heel shoes balances on a single heel. The heel is circular with a diameter 1 cm. The pressure exerted by the heel on the horizontal floor is then (Take g = 10 m s${}^{-2}$)

• A. 6.4 x 10${}^4$ Pa.
• B. 6.4 x 10${}^5$ pa
• C. 6.4 x 10${}^6$ Pa
• D. 6.4 x 10${}^7$ Pa

Answer 1

The correct option is C 6.4 x 10${}^6$ Pa

Here,$m=50kg,$

$D=1cm={10}^{-2}m$,

$g=10m{s}^{-2}$

$\therefore$ Pressure exerted by the heel on the horizontal floor is

$Pressure=\frac{Force}{Area}$ Force here is WEIGHT and area is area of circular portion of heel.

$P=\frac{F}{A}=\frac{mg}{\pi {\left(\frac{D}{2}\right)}^2}=\frac{4mg}{\pi D^2}$

$=\frac{4\times 50kg\times 10m{s}^{-2}}{3.14\times ({10}^{-2}m{)}^2}=6.4\times {10}^{6}pa$