Physics - Magnetism Question with Solution | TestHub

Radius of circular path: $r=\frac{mv}{qB}=\frac{1\times 12}{1\times 2}=6\mathrm{m}$

Time period: $T=\frac{2\pi m}{qB}=\pi \mathrm{s}$

Tracing the motion through the three field regions (into-plane, out-of-plane, into-plane), the particle spends a total time $t=\frac{4\pi }{3}\mathrm{s}$ in the magnetic field → (A) correct.

During this motion the velocity becomes parallel to the x-axis 6 times → (B) correct.

The separation between entry and exit points is not 6 m → (C) incorrect.

Net deviation of the particle when it emerges: $\frac{2\pi }{3}\mathrm{rad}$ → (D) correct.

Hence (A), (B) and (D).