Question

Define Electromagnetism.
(A). The study of attraction and repulsion between two magnets is called electromagnetism.
(B). The study of electric effects due to magnetic interaction is called electromagnetism.
(C). The study of magnetic effects produced due to electric current is called electromagnetism.
(D). The study of magnetic effects produced due to electric charges is called electromagnetism.

Answer 1

- Hint: A magnetic field is produced due to flowing of electric current through a coil or a wire. The electric current which produces this field is a result of electrical charges flowing through a wire in unit time. The term electromagnetism refers to the magnetism produced by electric current.

Complete step-by-step solution -
All of us have heard of magnetic fields being produced, due to a current flowing through a wire or a coil. The magnetic field produced by a solenoid is a perfect example of how an electric current through a coil produces a magnetic field along the axis of the coil. So, in this case, a magnetic effect is produced due to a current.
Also, from Faraday’s law of electromagnetic induction, we can see that a change in magnetic flux associated with a coil, induces an EMF in the coil. The direction of the EMF is determined by the polarity of the magnetic field. So, in this case, an electrical effect is caused due to the change in the magnetic field.
So, electromagnetism deals with both the points given above. So, a moving charge can produce a magnetic field similarly a magnetic field can produce an EMF.

So options (B) and (C) are both suitable answers to this question.

Note: The field electromagnetism deals with the electromagnetic force, which is a type of force common between charged particles. The electromagnetic force is the force experienced by a charged particle when it travels through an electric field.
We all have heard of Lorentz force, which is the force acting on a charged particle, with charge q and moving with a velocity v in an external electric and magnetic field. It is expressed mathematically as,
$$\overrightarrow{F}=q(\overrightarrow{E}+\overrightarrow{v}\times \overrightarrow{B})$$
Where
E is the electric field associated with the electromagnetic field.
B is the magnetic field associated with the electromagnetic field.
Electromagnetic waves are produced by accelerated charged particles, oscillating charged particles produce electromagnetic fields which produce a time-varying electromagnetic wave. These waves travel at a speed equal to the speed of light in vacuum.