The law of electricity and magnetism is used to

A crossed electric and magnetic field is used in…………………….

State few laws relating electric and magnetic fields.

The law which states that the variations of electric field causes magnetic field is

The law which states that the variations of electric field causes magnetic field is

Which law is useful to determine relation between current and magnetic fields due to it.

In which of the following electrical appliances the principle of the magnetic effect of electric current is used?