Discussion
A hydraulic press has a ram of 20cm diameter and a plunger of 5cm diameter .The force required at the plunger to lift a weight of 16 × 104 N shall be?
Answer: D
The force at the plunger is \(1 \times 10^{4}\ \text{N}\).
By Pascal's law the pressure is the same under the plunger and the ram, so the forces are in the ratio of the areas, that is of the squares of the diameters:
\[ \begin{aligned} F &= W \left(\frac{d}{D}\right)^{2} = 16 \times 10^{4} \times \left(\frac{5}{20}\right)^{2} \\ &= \frac{16 \times 10^{4}}{16} = 1 \times 10^{4}\ \text{N} \end{aligned} \]
\(4 \times 10^{4}\) N uses the ratio of diameters instead of areas. \(64 \times 10^{4}\) and \(256 \times 10^{4}\) N multiply instead of divide, which would make the press a force reducer.
Post your comment
Please log in or register to post a comment.
Examination Categories
- SSC Exams
- Banking Exams
- Teaching Exams
- Civil Services Exams
- Railways Exams
- Engineering Recruitment Exams
- Defence Exams
- State Government Exams
- Police Exams
- Insurance Exams
- Nursing Exams
- Other Government Exams
- NRA CET
- PG Entrance Exams
- Campus Placement
- MBA Entrance Exams
- CUET and UG Entrance
- Judiciary Exams
- Regulatory Body Exams
- Software Development