Question

A particle of mass m and charge q, moving with velocity V enters Region II normal to the boundary as shown in the figure. Region II has a uniform magnetic field B perpendicular to the plane of the paper. The length of the Region II is l. Choose the correct choice(s).

• A. The particle enters Region III only if its velocity V$>\frac{qlB}{m}$
• B. The particle enters Region III only if its velocity V$<\frac{qlB}{m}$
• C. Path length of the particle in Region II is maximum when velocity $V=\frac{qlB}{m}$
• D. Time spent in Region II is same for any velocity V as long as the particle returns to Region I

Answer 1

Answer: (A), (C), (D)

The correct options are
A The particle enters Region III only if its velocity V$>\frac{qlB}{m}$
C Path length of the particle in Region II is maximum when velocity $V=\frac{qlB}{m}$
D Time spent in Region II is same for any velocity V as long as the particle returns to Region I