Concepts Of Physics MCQ Edition [Volume 2]PhysicsMagnetic Field
When a charged particle at rest experiences zero electromagnetic force,
Options
- Athe electric field must be zero
- Bthe magnetic field must be zero
- Cthe electric field might or might not be zero
- Dthe magnetic field might or might not be zero
Correct answer
D. the magnetic field might or might not be zero
Step-by-step solution
The electromagnetic force on a charged particle is given by the Lorentz force equation: F = q( E + v B ) Since the particle is at rest, its velocity v = 0 . The magnetic force component is q( v B ) = 0 , irrespective of the magnetic field B . The total force reduces to F = q E . Given that the total electromagnetic force is zero, we have q E = 0 . Since the particle is charged ( q 0 ), the electric field E must be zero. The magnetic field B does not exert any force on a particle at rest, so it might or might not be