MCQ
Pick out the statement which is not true
  • A
    IR radiations are used for long distance photography
  • IR radiations arise due to inner electron transitions in atoms
  • C
    IR radiations are detected by using a bolometer
  • D
    Sun is the natural source of IR radiation

Answer

Correct option: B.
IR radiations arise due to inner electron transitions in atoms
b
The primary source of infrared radiation is heat or thermal radiation. This is the radiation produced by the motion of atoms and molecules in an object. When an object is not quite hot enough to radiate visible light, it will emit most of its energy in the infrared.

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