Topic: Fluid Mechanics
A hydraulic press has a ram of 30 cm diameter and a plunger of 4.5 cm diameter. Find the weight lifted by hydraulic press when force applied at plunger is 500 N.
- A. 3.33 KN
- B. 22.22 N
- C. 3.33 N
- D. 22.22 KN
Answer: D. 22.22 KN
Explanation: According to Pascal's law, pressure is transmitted equally. $P = \frac{F}{A_{plunger}} = \frac{W}{A_{ram}}$.
Therefore, $W = F \times \left(\frac{D_{ram}}{D_{plunger}}\right)^2 = 500 \times \left(\frac{30}{4.5}\right)^2 = 500 \times \left(\frac{20}{3}\right)^2 = 500 \times \frac{400}{9} = 22222.22~N = 22.22~KN$.