JEE Mains · Physics · STD 12 - Electromagnetic waves
- JEE Mains 2023
- Medium
- MCQ
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:
Pick an option to check your answer.
Answer & Solution
Correct Answer
(A) \(A\) is false but \(R\) is true
Step-by-step Solution
Detailed explanation
Optical communication is performed in the frequency range of \(1\,THz\) to \(1000\,THz\).
(Microwave to \(UV\))
So,\(EM\) waves used for optical communication have shorter wavelength than that of microwaves used in \(RADAR.\)
Also, \(v_{\text {INFRARED }}>v_{\text {MICROWAVE }}\)
\(\therefore\) Infrared \(EM\) waves are more energetic than microwave
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