Pick out the statement which is not true.

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(B) Infrared $(IR)$ radiations are electromagnetic waves with wavelengths longer than visible light. They are primarily produced by the thermal agitat

Vedclass · Accepted Answer

$IR$ radiations arise due to inner electron transitions in atoms.

Vedclass · Answer

(B) Infrared $(IR)$ radiations are electromagnetic waves with wavelengths longer than visible light. They are primarily produced by the thermal agitation of atoms and molecules in a substance,which is why they are often called heat rays. Option $A$ is true because $IR$ rays have longer wavelengths and can penetrate through haze and fog,making them useful for long-distance photography. Option $B$ is false because $IR$ radiations arise due to the vibration and rotation of molecules,not due to inner electron transitions (which typically produce $X$-rays). Option $C$ is true as a bolometer is a device used to detect and measure the intensity of incident electromagnetic radiation. Option $D$ is true as the Sun emits a significant portion of its energy in the infrared spectrum.

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