Question

Statement I Infrared waves are sometimes referred to as heat waves.
Statement II Water molecules present in most materials readily absorb infrared waves. After absorption, their thermal motion increases, that is they heat up and heat their surroundings.

• A. Both Statement I and Statement II are correct and Statement II is the correct explanation of Statement I.
• B. Both Statement I and Statement II are correct but Statement II is not the correct explanation of Statement I.
• C. Statement I is correct but Statement II is incorrect.
• D. Statement I is incorrect but Statement II is correct.

Answer 1

Answer: (A)

Infrared waves are sometimes referred to as heat waves. This is because water molecules present in most materials readily absorb infrared waves (many other molecules, e.g., $C{O}_2,N{H}_3$, also absorb infrared waves). After absorption, their thermal motion increases, that is, they heat up and heat their surroundings.