# What pressure is exerted on the soil by a boy weighing 45 kg, who holds a watermelon

**What pressure is exerted on the soil by a boy weighing 45 kg, who holds a watermelon weighing 7.5 kg in his hands, if the area of one of his soles is 150 cm2**

Given:

m1 = 45 kilograms – the weight of the boy;

m2 = 7.5 kilograms – the mass of a watermelon that a boy is holding in his hands;

s = 150 cm2 = 0.015 m2 – the area of one boy’s sole;

n = 2 – total number of soles.

It is required to determine P (Pascal) – the pressure exerted by the boy on the soil.

Let’s find the total mass of the boy and the watermelon:

m = m1 + m2 = 45 + 7.5 = 52.5 kilograms.

Then the force of gravity will be equal to:

F = m * g (where g = 10 N / kg is an approximate value);

F = 52.5 * 10 = 525 Newton.

The total area of the soles will be equal to:

S = s * n = 0.015 * 2 = 0.03 m2.

Then the pressure will be equal to:

P = F / S = 525 / 0.03 = 17500 Pascal (17.5 kPa).

Answer: the boy exerts a pressure of 17.5 kPa on the soil.