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3 years ago

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the sole of a tennis shoe has a surface area of 0.0290 m^2. if it is worn by a 65.0 kg person, what pressure does the shoe exert

on the ground?

1 answer:

AURORKA [14]3 years ago

5 0

Answer: 21965.517 Pa

Explanation:

Pressure $P$ is the force $F$ exerted by a gas, a liquid or a solid on a surface (or area) $A$ , its unit is Pascal $Pa$ which is equal to $N/m^{2}$ and its formula is:

$P=\frac{F}{A}$ (1)

In this case we have the surface of a sole of a tennis shoe:

$A=0.0290 m^{2}$ (2)

And the mass $m$ of the person who wears it:

$m=65 kg$

On the other hand, we know the weight is the force $F$ the Earth exerts on people and objects due gravity $g$ :

$F=m.g=(65 kg)(9.8m/^{2})$

$F=637N$ (3)

Substituting (2) and (3) in (1):

$P=\frac{637N}{0.0290 m^{2}}$ (4)

Finally:

$P=21965.517 Pa$ This is the pressure the shoe exert on the ground

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