JEE Main 2021PhysicsCommunication SystemEasyMCQ

JEE Main 2021 — Communication System Question with Solution

JEE Main 2021 (27 Aug Shift 2)

Question

An antenna is mounted on a 400 m tall building. What will be the wavelength of signal that can be radiated effectively by the transmission tower upto a range of 44 km ?

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Show full solutionCorrect option: A
Correct answer
A605 m

Step-by-step explanation

d=2RhT

⇒44×103=2×6400×103×hT

⇒hT=151.25 m

∵ lantenna≥λ4

⇒λ≤4l

considering, hT=1= length of antenna

λ=4×151.25=605 m

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About this question

This is a previous-year question from JEE Main 2021, covering the Communication System chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.