A particle having the same charge as of electron moves in a circular path of radius 0.5 cm under the influence of a magnetic field of 0.5 T. If an electric field of 100V/m makes it to move in a straight path, then the mass of the particle is ( Given charge of electron `= 1.6 xx 10^(-19)C`)

Options

A. `9.1xx10^(-31)kg`
B. `2.0xx10^(-24)kg`
C. `1.6xx10^(-27)kg`
D. `1.6xx10^(-19)kg`

Answer

B

Explanation

`r=(mv)/(qB)`…………….i
and `qE=qvB` …………ii `implies V=E/B`
From i and ii
`r=m/qxx((E//B))/B=(mE)/(qB^(2))impliesm=(qB^(2)r)/E=2xx10^(-24)kg`