JEE Main2015PhysicsMagnetic Effects of CurrentActual
A proton (mass m ) accelerated by a potential difference V flies through a uniform transverse magnetic field B . The field occupies a region of space by width d . If α be the angle of deviation of proton from the initial direction of motion (see figure), the value of sin ⁡ α will be:
Options
- AB 2 q d m V
- BB d q 2 m V
- CB d q 2 m V
- Dq V B d 2 m
Correct answer
B. B d q 2 m V
Step-by-step solution
Due to potential difference V speed acquired by proton is v 0 , ⇒ q V = 1 2 m v 0 2 = K ∵ Radius,   R = m v 0 q B = 2 m K q B ∵ K = q V R = 2 m e V q B sin α = d R = d q B 2 m e V = B d q 2 m V