A charged particle moving at right angles to a uniform magnetic field moves in a circle because:

  1. the field does work on it
  2. the force is parallel to its velocity
  3. the magnetic force is always perpendicular to its velocity
  4. its charge changes
Answer

C) the magnetic force is always perpendicular to its velocity

A perpendicular force provides centripetal force. SLO P-11-B-10 · Understanding

Physics MCQ · More Circular and Rotational Motion MCQs · Practise