Question

Light is a transverse wave because it shows

• A. Reflection
• B. Polarization
• C. Interference
• D. Diffraction

Hint:

Remember that reflection, refraction, interference, and diffraction are common to all waves. Polarization is the exclusive property of transverse waves. This makes it the key phenomenon to distinguish between transverse and longitudinal waves.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Waves can be classified as transverse or longitudinal. In a transverse wave, the oscillations are perpendicular to the direction of wave propagation. In a longitudinal wave, the oscillations are parallel to the direction of propagation. The question asks for the phenomenon that uniquely demonstrates the transverse nature of light.
Step 2: Detailed Explanation:
(A) Reflection, (C) Interference, and (D) Diffraction are general properties of all types of waves, both transverse and longitudinal. For example, sound waves, which are longitudinal, also exhibit reflection (echo), interference, and diffraction. Therefore, these phenomena prove that light has wave properties, but they do not specify its type.
(B) Polarization is the process of restricting the oscillations of a wave to a single plane. A transverse wave has oscillations in a plane perpendicular to its motion, which allows these oscillations to be filtered or restricted to a specific orientation. A longitudinal wave, whose oscillations are along the direction of motion, has no such component to filter. Therefore, only transverse waves can be polarized.
Step 3: Final Answer:
Since light can be polarized (e.g., using a Polaroid filter), it must be a transverse wave. Polarization is the definitive proof of the transverse nature of light. Option (B) is correct.