An electron ( ) enters a magnetic field with speed at an angle of to the field

PHYSICS · Single correct · CBSE · Physics · Moving Charges and Magnetism · Moving Charges and Magnetism

Problem

An electron (

m=9.1\times10^{-31}\,\text{kg}

) enters a

0.05\,\text{T}

magnetic field with speed

3.0\times10^{7}\,\text{m s}^{-1}

at an angle of

30^{\circ}

to the field. The pitch of its helical path is approximately (a)

0.036\,\text{m}

(b)

0.018\,\text{m}

(c)

0.013\,\text{m}

(d)

0.026\,\text{m}