Motion for induction can come from _ _ _ _ _ _ _ _ _.?

Question

a) alternating current
b) two switches conneceted by a magnet
c) expanding and collapsing of a magnetic field
d) current through a wire

Answer 1

Electromagnetic induction is the production of voltage across a conductor situated in a changing magnetic field or a conductor moving through a stationary magnetic field.

Faraday found that the electromotive force (EMF) produced around a closed path is proportional to the rate of change of the magnetic flux through any surface bounded by that path.

In practice, this means that an electrical current will be induced in any closed circuit when the magnetic flux through a surface bounded by the conductor changes. This applies whether the field itself changes in strength or the conductor is moved through it.


c) expanding and collapsing of a magnetic field

Answer 2

All of them.
a) The magnetic field around a AC conductor will be expanding and collapsing.
b) Any interuption (switching) of an electric current will cause the expanding and collapsing of a magnetic field.
c) Expanding and collapsing of a magnetic field.
d) Any change in a current through a wire or physical movement of the wire will cause changing of a magnetic field.