Question

Which of following can not be polarized

• A. Radio waves
• B. Ultraviolet rays
• C. Infrared rays
• D. Ultrasonic waves

Answer 1

The correct option is D

Ultrasonic waves

Explanation of correct answer

(D) Ultrasonic waves

Plane polarized light

• Plane polarized light is made up of waves with the same direction of vibration for all of them.
• Some materials have the capacity to filter out all vibrations save those in a single plane, resulting in plane polarized light.
• The most well-known example is the material used to make Polaroid sunglasses.

Ultrasonic waves

• Ultrasonic waves are sound waves with a frequency greater than $20\mathrm{kHz}$.
• That cannot be polarized due to their longitudinal nature.

Explanation of incorrect answer

(A) Radio waves

• Radio waves like electromagnetic waves can be polarized.
• To create sound waves, these devices receive radio waves and transform them into mechanical vibrations in the speaker.

(B) Ultraviolet rays

• Ultraviolet waves like electromagnetic waves can be polarized.
• It accounts for around $10\%$of the Sun's total electromagnetic radiation output.

(C) Infrared rays

• Infrared waves like electromagnetic waves can be polarized.
• The term "infrared" refers to wavelengths ranging from $1$ millimeters to $700$ nanometers, which is the nominal red edge of the visible spectrum.

Therefore, the correct option is (D) Ultrasonic waves.