A man exerts a pressure of 2.8 x 10³Nm‾² on the ground and has 4 x 10−²m² of his feet in contact with the ground. The weight of the man is?

A. 102N
B. 70N
C. 140N
D. 112N

Correct Answer:

Option D – 112N

Explanation

Pressure = Force / Area = Weight of the man / Area of his feet
=> 2.8 x 10³ = Weight of the man / 4 x 10^-2
∴ Weight of the man = 2.8 x 10³ x 4 x 10^-2
= 112N