Correct Answer - A::B::C
The distance travelled by an
atom of helium in `1/500sec` (time
between two succesive
collision) is 2m. Therefore root
mean square speed
`C_(rms)=distance/time=2/(1//500)=1000m//s`
(a) But `C_(rms)=sqrt((3RT)/M)`
`rArr1000=((3xx25//3xxT)/(4xx10^-3) rArr T=160K`
(b) Average kinetic energy of an atom of a monoatomic
gas =`3/2kT`
`:. E_(av)=3/2kT=3/2xx(1.38xx10^-23)xx160`
`=3.312xx10^-21 Joules`
(c) From gas equation `PV=m/MRT`
`m=(PVM)/(RT)=(100xx1xx4)/(25//3xx160) rArr m=0.3012gm`