In a car lift compressed air exerts a force FF_1 on a small piston having a radius of 5.0 cm, This pressure is transmitted to a second piston of radius 15cm [Fig.10.7]. If the mass of the car to be lifted is 1350 kg. calculate F_1 What is the pressure necessary to accomplish this task?

In a car lift compressed air exerts a force FF_1 on a small piston hav

1.	In a car lift compressed air exerts a force FF_1 on a small piston having a radius of 5.0 cm, This pressure is transmitted to a second piston of radius 15cm [Fig.10.7]. If the mass of the car to be lifted is 1350 kg. calculate F_1 What is the pressure necessary to accomplish this task?
Answer» Solution :Since pressure is TRANSMITTED UNDIMINISHED throughout the fluid, `F_1=A_1/A_2 F_2=(pi(5 TIMES 10^-2 m)^2)/(pi(15 times 10^-2 m)^2)(1350 kg times 9.8 ms^-2)` =1470 N `=1.5 times 10^3 N` The air pressure that will produce this force is `P=F_1/A_1=(1.5 times 10^3 N)/(pi(5 times 10^-2)^2 m)=1.9 times 10^5 Pa` This is almost double the ATMOSPHERIC pressure. Hydraulic brakes in automobiles also WORK on the same principle. When we apply a little force on the pedal with our foot the master piston.