Question

A positively charged particle moving with constant speed due east enters a region of uniform magnetic field directed vertically upwards this particle will-

• A. Get deflected vertically upwards direction
• B. move in a circular path with its increased speed
• C. move in a circular path with its unchanged speed
• D. Be moving in a straight part with the same speed

Answer 1

The correct option is C move in a circular path with its unchanged speed

By right-hand rule force, $\overrightarrow{F}=q\overrightarrow{V}\times \overrightarrow{B}$ will be towards south so the charge will start moving in a circular path.

As the force is in the perpendicular direction so it will not do any work so speed will not change.

Option C is correct.