Question

Why magnetic force do no work

Answer 1

Answer:

Because the magnetic force on a moving charge is perpendicular to the velocity, the work done by a magnetic force is zero. An interesting example of this is the case of a rotating wheel carrying point charges in a magnetic field: ... The coil on the left makes a magnetic field to the right.

Answer 2

Answer:

Because the magnetic force on a moving charge is perpendicular to the velocity, the work done by a magnetic force is zero.