Question

A piston in a gas supply pump has an
area of 500 cm2 and it moves a distance
of 30 cm during one stroke. The pump
moves the gas against a fixed pressure
of 4000 Pa. The work done by the piston
during on strikes is
A. 60 joule
B. 70 joule
C. 55 joul
D. None

Answer 1

Answer:

A. 60 Joule

Explanation:

First find the force given the pressure and area.

F = AP

F = 500 cm² × (1 m / 100 cm)² × 4000 N/m²

F = 200 N

Now find the work:

W = Fd

W = 200 N × 30 cm × (1 m / 100 cm)

W = 60 J

Answer 2

Option A is the correct answer.

Explanation:

Pressure is the ratio of normal force to the area.

$\texttt{Pressure = }\frac{\texttt{Normal force}}{\texttt{Area}}$

Force = Pressure x Area

Area = 500 cm² = 0.05 m²

Pressure = 4000 Pa

Force = 0.05 x 4000 = 200 N

We know that

                Work done = Force x Displacement

                 W = F x d

                 Displacement, d = 30 cm = 0.3 m

                 W = 200 x 0.3 = 60 Joules.

Option A is the correct answer.