Which instrument is most suitable for the detection of the radiation emitted by a TV remote control?
A Radio receiver
B Blackened thermometer
C Geiger Muller Tube
D Fluorescent material
I know that there is an LED behind the darkened plastic of a conventional TV remote control (eaarly ones used sound waves, some high end TV receivers use radio frequencies)
And the LED transmits light in the infra-red spectrum. You can't see it, but some animals can.
A radio receiver is conventionally designed to pick up radio waves in a different part of the electro-magnetic spectrum
Geiger-Muller tube senses ionising radiation (alpha beta gamma particles) but your tv remote is not a radio active source.
Fluorescent material is usually sensitive to light in the ultra-violet spectrum, which it re-radiates back [to your eyes] in the visible light spectrum.
In practical real life, a tv remote issues so little infrared energy, that a blackened thermometer will not be able do detect it accurately, but this is the most correct answer.
radio R-311 soviet military receiver R-311 tube radio