Physics

Problem

A beam of protons with speed

4 \times 10^5 \text{ ms}^{-1}

enters a uniform magnetic field of

0.3 \text{ T}

at an angle of

60^\circ

to the magnetic field. The pitch of the resulting helical path of protons is close to : (Mass of the proton

= 1.67 \times 10^{-27} \text{ kg}

, charge of the proton

= 1.6 \times 10^{-19} \text{ C}

) a.

2 \text{ cm}

5 \text{ cm}

12 \text{ cm}

4 \text{ cm}