A flask has 10 molecules out of which four molecules are moving at `7 ms^(-1)` and the remaining ones are moving at same speed of `X ms^(-1)`. If rms of the gas is `5 ms^(-1)`, what is `X` ?

Answer

3

Explanation

`3ms^(-1)`
`u_(rms)=sqrt((u_(1)^(2)N_(1)+u_(2)^(2)N_(2))/(N_(1)+N_(2)))impliesu_(rms)^(2)=(u_(1)^(2)N_(1)+u_(2)^(2)N_(2))/(N_(1)+N_(2))`
`25=(4xx7^(2)+u_(2)^(2))/(10)impliesU_(2)=sqrt((54)/(6))=3ms^(-1)`