Question
Question: The nature of electromagnetic wave is : (A) longitudinal (B) longitudinal stationary (C) trans...
The nature of electromagnetic wave is :
(A) longitudinal
(B) longitudinal stationary
(C) transverse
(D) transverse stationary
Solution
Hint
The electromagnetic waves are the synchronised oscillations of the electric and magnetic fields which are propagating with the speed of light. They are transverse waves moving with a certain phase velocity.
Complete step by step answer
The electromagnetic waves are created as a result of the vibrations between an electric and a magnetic field. In other words, they are composed of oscillating electric and magnetic fields. The electric and magnetic field vectors are perpendicular to each other and they both are also perpendicular to the direction of propagation of the wave.
In vacuum, the electromagnetic waves travel with the speed of light that is 3×108m/s. So we can say that the electromagnetic waves are not stationary waves.
And these waves are measured with the help of their amplitude and wavelength. So this is why the waves are termed as transverse. So the electromagnetic waves are transverse waves.
Hence the correct answer is option (C).
Note
A stationary wave is also called a standing wave. These kinds of waves do oscillate with time but do not move in space. At any point in space, the peak amplitude of oscillation of a standing wave is constant with time. A standing wave can occur when 2 waves which are travelling in opposite directions interfere with each other.
Longitudinal waves are those in which the particles of the medium move in a direction which is perpendicular to the direction in which the wave moves. They travel through a medium by producing compressions and rarefactions. The best example of longitudinal waves is the sound waves travelling through the air.