A hydraulic automobile lift is designed to lift cars with a maximum mass of 3000 kg. The area of cross-section of the piston carrying the load is 425 cm2. What maximum pressure would the smaller piston have to bear?
Maximum mass of a car that can be lifted (m) = 3000 kg
Area of cross section of piston carrying the load (A1) = 452 cm2
= 0.0452 m2
Maximum force exerted by the car due to its weight (F) = mg
= 3000kg × 9.8m/s2
= 29400 kgm/s2
Pressure on the piston lifting the car P = F/A
= 
= 6.504 × 105 Pa
Pressure is transmitted equally in all the directions of a fluid. Therefore the maximum pressure on the smaller piston is 6.504 × 105 Pa.
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