Question

An electromagnetic wave is propagating along the $Y$ axis. Then
(A) oscillating electric field is along $X$ axis and oscillating magnetic field is along $Y$axis
(B) oscillating electric field is along $Z$ axis and oscillating magnetic field is along $X$axis
(C) both oscillating electric and magnetic fields are along $Y$ axis, but the phase difference between them is ${90^\circ }$
(D) both oscillating electric and magnetic fields are mutually perpendicular in arbitrary direction

Answer 1

Hint: The vibrations between both the magnetic and electric field will lead to the formation of electromagnetic waves. The magnetic and electric fields will be in phase with each other. So, the angle between both the magnetic field and the electric field is ${90^\circ }$.

Complete Step by step solution:
The electromagnetic radiation is the radiation which consists of the electromagnetic waves, which are grouped oscillations of electric field and magnetic field, that travels at the speed of light in the vacuum. The oscillations of electric fields and magnetic fields are perpendicular to each other and perpendicular to the direction of propagation of electromagnetic waves. Usually an electromagnetic wave is propagating in the outward direction from the source. And it will travel at the speed of light. The source created oscillating electric and magnetic fields. They would be perpendicular to each other and would travel from the source. The electromagnetic waves became transverse waves hence both the electric and magnetic fields are perpendicular to the direction of the propagation of the wave travels. Therefore, an electromagnetic wave is propagating along the $Y$ axis, then the oscillating electric field is along the $Z$ axis and the oscillating magnetic field is along the $X$axis.

The answer is option B.

Note: The key factors to understand the electromagnetic waves are that the oscillating electric field produces an oscillating magnetic field. An oscillating magnetic field will produce an oscillating electric field. The oscillation of the two fields of the electric field and the magnetic field is perpendicular to each other.