A proton is moving perpendicular to a uniform magnetic field of 2.5 tesla with 2 MeV kinetic energy. The force on proton is _______N. (Mass of proton= `1.6 xx 10^(-27)` kg, charge of proton `=1.6 xx 10^(-19)` C)

Options

A. `3xx10^(-12)N`
B. `8xx10^(-10)N`
C. `8xx10^(-12)N`
D. `8xx10^(-12)N`

Answer

C

Explanation

`E=2xx1.6xx10^(-19)xx10^(6)=3.2xx10^(-13)J`
`E=1/2mv^(2)=v=sqrt((2E)/m),F=B qv sin 90^(@)=Bq sqrt((2E)/m)=8xx10^(-12)N`