A portable hydraulic jack is used to lift one side of a car for tyre replacement
PHYSICS · Multi-part · CBSE · Physics · Mechanical Properties of Fluids · Mechanical Properties of Fluids
Problem
A portable hydraulic jack is used to lift one side of a car for tyre replacement. The jack contains two coaxial pistons. The smaller piston has diameter 1.5cm and the larger piston has diameter 12cm. When the jack is operated, a load of 1.2×104N has to be lifted.
(i) Assuming an ideal (loss-free) system, calculate the theoretical force that must be applied on the smaller piston to begin lifting the car.
(ii) In practice, frictional and leakage losses limit the efficiency of the jack to 85%. Determine the actual force that the operator must apply.
(iii) If the operator is able to exert a maximum force of 220N, discuss whether the jack will successfully raise the car. Justify quantitatively.