Question
In He-Ne laser, metastable state exists in

Answer

(b)

fact

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Assertion : Dipole oscillations produce electromagentic waves.

Reason : Accelerated charge produces electromagnetic waves.

Given below are two statement: one is labelled as Assertion $A$ and the other is labelled as Reason $R.$

Assertion $A:$ $EM$ waves used for optical communication have longer wavelengths than that of microwave, employed in Radar technology.

Reason $R$ : Infrared $EM$ waves are more energetic than microwaves, (used in Radar)

In the light of given statements, choose the correct answer from the options given below: