Given, At `27^(@)C,` root meann square speed
`v_(rms)=100ms^(-1)`
`(v_(rms_(1)))=sqrt((3p_(1))/(d_(1)))=sqrt((3p_(1)V_(1))/(M))`
According to ideal gas equation
`(p_(1)V_(1))/(T_(1))=(p_(2)V_(2))/(T_(2))` `Rightarrow" " (V_(1))/(V_(2))=(p_(2)T_(1))/(p_(1)T_(2))=(2xx300)/(400)=(3)/(2)`