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Questions
Why are infra-red waves often called heat waves? Explain.
Why are infrared waves often called heat waves? Given their one application.
Solution
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, for example, CO2, and NH3, also absorb infrared waves). After absorption, their thermal motion increases, that is, they heat up and heat their surroundings.
Infrared waves are used in burglar alarms, security lights and remote controls for television and DVD players.
Notes
Students should refer to the answer according to their questions.
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