What type of electromagnetic radiation is used in the remote control of a television?
- AInfrared
- BUltraviolet
- CVisible
- DNone of the above
Show answer and explanation
Correct answer: (a) Infrared
Explanation
TV remotes transmit signals using infrared (IR) radiation, whose wavelength is longer than that of visible light.
IR is invisible to the human eye yet easily emitted by a cheap LED and detected by a sensor.
Ultraviolet is harmful and high-energy, making it unsuitable for everyday remotes.