Q. Radius of one arm of hydraulic lift is four times of radius of other arm. What force should be applied on narrow arm to lift 100kg?
A) 26.5 N
B) 62.5 N
C) 6.25 N
D) 8.3 N
Explanation
(b) By Pascal’s law
$\frac{F}{A} = \frac{f}{a}$
$or\ \ f = \frac{Fa}{A} = \frac{100g \times (\pi\ r)^{2}}{(\pi \times 4r)^{2}}$
$= 6.25g = 62.5N$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.