Momentum of an electron, when a potential difference of 500 volt is applied across the electrodes of CRT in SI units is :

Options

A. `1.6xx10^(-19)`
B. `1.9xx10^(-27)`
C. `9.1xx10^(-27)`
D. `1.2xx10^(-23)`

Answer

D

Explanation

p=mv
Now `eV=(1)/(2)mv^(2)`
`:. V^(2)=(2eV)/(m) rArr v= sqrt((2eV)/(m))`
`:. P=m sqrt((2eV)/(m))= sqrt(2meV)==1*2xx10^-(-23)` SI units