Question

The transverse nature of electromagnetic waves is confirmed by the phenomenon of

• A. diffraction
• B. polarization
• C. photoelectric effect
• D. interference
• E. total internal reflection

Hint:

Only transverse waves can be polarized. This is the strongest evidence for the transverse nature of light.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
This question asks which wave phenomenon uniquely demonstrates that electromagnetic (EM) waves are transverse. A transverse wave is one in which the oscillations are perpendicular to the direction of wave propagation. A longitudinal wave is one in which the oscillations are parallel to the direction of propagation.
Step 2: Detailed Explanation:
Let's analyze the given phenomena:

(A) Diffraction and (D) Interference: These are characteristic properties of all types of waves, including transverse waves (like light) and longitudinal waves (like sound). They show that light has wave properties, but they do not provide information about the orientation of the wave oscillations.

(C) Photoelectric effect: This phenomenon demonstrates the particle nature of light (photons), not its wave nature.

(E) Total internal reflection: This is explained by ray optics (Snell's law) and wave optics, but it does not reveal the transverse nature of the wave.

(B) Polarization: Polarization is the process of restricting the oscillations of a wave to a specific plane. In an unpolarized transverse wave, oscillations occur in all possible directions perpendicular to the direction of motion. A polarizer can filter these oscillations, allowing only those in a particular plane to pass through. Longitudinal waves cannot be polarized because their oscillations have only one possible direction—along the direction of wave propagation. Since EM waves can be polarized, they must be transverse waves.

Step 3: Final Answer:
The phenomenon of polarization is exclusive to transverse waves and thus confirms the transverse nature of electromagnetic waves. This corresponds to option (B).