Question

The area of cross-section of the pump plunger and press plunger of a hydraulic press are 0.02 m² and 8 m² respectively. If the hydraulic press overcomes a load of 800 kgf. Calculate the force acting on pump plunger.

(1) 2 kgf 

(2) 5 kgf 

(3) 0.25 kgf 

(4) 2.5 kgf

Answer 1

Correct option is (1) 2 kgf 

Load on the press plunger \(=\mathrm{L}=800\, \mathrm{kgf}\)

Let the effort acting on the pump plunger \(=\mathrm{E}\)

Area of cross-section of pump plunger \(=\mathrm{A}_1=0.02 \mathrm{~m}^2\)

Area of cross-section of press plunger \(=A_2=8 \mathrm{~m}^2\)

Now, \(\frac{\mathrm{L}}{\mathrm{E}}=\frac{\mathrm{A}_2}{\mathrm{~A}_1}\)

\(\frac{800}{\mathrm{E}}=\frac{8}{0.02}=\frac{800}{2}=400\)

\(E=\frac{800}{400}=2\, \mathrm{kgf}\)

\(\Rightarrow\) Force acting on the pump plunger \(= 2\, \mathrm{kgf}\).