A cylinder contained `10kg`of gas at pressure `10^(7) N / m^(2)`. The quantity of gas taken out of cylinder if final pressure is `2.5 xx 10^(6) N//m^(2)` is (Assume temperature of gas is constant)

Options

A. `9.5 ` kg
B. `7.5` kg
C. `14.2` kg
D. zero

Answer

B

Explanation

`(P_(1))/(P_(2))=(rho_(1))/(rho_(2))=(m_(1))/(m_(2))`
`m_(2)=(P_(2))/(P_(1))xxm_(1)=(2.5xx10^(6))/(10^(7))xx10=2.5 kg`
Mass of gas taken out `=10-2.5=7.5 kg`