An electric field of 1500 V/m and a magnetic field of 0.40 Wb/`m^(2)` act on a moving electron. The minimum uniform speed along a straight line, the electron could have is

Options

A. `16xx10^(15) ms^(-1)`
B. `6xx10^(-16) ms^(-1)`
C. `3.75 xx10^(3) ms^(-1)`
D. `3.75 xx10^(2) ms^(-1)`

Answer

C

Explanation

When electron moves in both electric and magnetic fields then
`qE=qvB`
so speed of electron
`V=(E )/(B)=(1500)/(0.40 )=3750 ms^(-1) rarr V=3.75 xx10^(3) ms^(-1)`