The density of a gas filled in electric lamp is `0.75kg//m^(3)` . After the lamp has been switched on, the pressure in it increases from `4xx10^(4)` Pa to `9xx10^(4)` Pa. What is increases in `u_("rms")` ?

Options

A. 100
B. 200
C. 300
D. None of these

Answer

b

Explanation

(b) `U_(1)=sqrt((3P_(1))/(d_(1)))`
`:. /_\U_("rms")=sqrt((3)/(d))(sqrt(P_(2))-sqrt(P_(1)))`
`=sqrt((3)/(0.75))(300-200)`
`=sqrt(4)xx100=200`