Question

The mass of a box is 20 kg and its dimensions are 100cm x 50cm x 20cm. Find the pressure
exerted by the brick on ground, if it is made to reset with its side of dimensions as
a) 100cm x 50 cm
b) 50cm x 20 cm
c) 100 cm x 20 cm


please help, I can't understand this at all​

Answer 1

Explanation:

Pressure acting on a surface is equal to the force exerted per unit area of the surface.

Pressure = Force / Area

In this case, the force will be exerted by the mass which is equal to its weight.

Assuming g = 10 ms^-2

F = mg = 20 × 10 = 200 N

Calculating the areas in squared metres:

a) Area = 1 × 0.5 = 0.5 m^2

P = F/A = 200/0.5 = 400 Pa

b) Area = 0.5 × 0.2 = 0.1 m^2

P = 200/0.1 = 2000 Pa

c) Area = 1 × 0.2 = 0.2 m^2

P = 200/0.2 = 1000 Pa