A piston of cross-sectional area 100 `cm^(2)` is used in a hydraulic press to exert a force of 107 dyne on the water. The cross-sectional area of the other piston which supports a truck of mass 2000 kg is :

Options

A. `9.8xx10^(2)cm^(2)`
B. `9.8xx10^(3)cm^(2)`
C. `1.96xx10^(3)cm^(2)`
D. `1.96xx10^(4)cm^(2)`

Answer

D

Explanation

Pressure on the first piston = `(10^(7))/100=10^(5)` dyne/c`m^(2)`
Let A be the cross sectional area of the other piston.
Then the pressure on this piston =`(2000xx1000xx980)/A`
Since the two pressures are equal.
`therefore(2000xx1000xx980)/A=10^(5)`
or `A=19600cm^(2)=1.96xx10^(4)cm^(2)`
Correct choice is (d).