The rms speed of particle of mass `5 xx 10^(-17) kg`. In their random motion in air at NTP will be (Boltzmann's constant) `K = 1.38 xx 10^(-23) J//K`

Options

A. `15 xx 10 + m//s`
B. `15 xx 10^(-3) m//s`
C. `10 xx 10^(-2)`
D. `1.5 xx 10^(2) m//s`

Answer

B

Explanation

Given Mass of the particles `m = 5xx10^(-17)kg`
Absolute temperature = 273K
The rms speed of the particle is given by
`v_(rms) = sqrt((3RT)/(m)) = sqrt((3xx1.38xx10^(-23)xx273)/(5xx10^(-17)))`
`=sqrt(226xx10^(-6))=15xx10^(-3)`.