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Question
An EM wave radiates outwards from a dipole antenna, with E0 as the amplitude of its electric field vector. The electric field E0 which transports significant energy from the source falls off as ______.
Options
`1/r^3`
`1/r^2`
`1/r`
remains constant
Solution
An EM wave radiates outwards from a dipole antenna, with E0 as the amplitude of its electric field vector. The electric field E0 which transports significant energy from the source falls off as `underline(1/r)`.
Explanation:
A diode antenna radiates the electromagnetic waves outwards. The amplitude of electric field vector (E0) which transports significant energy from the source falls intensity inversely as the distance (r) from the antenna, i.e., `E_0 oo 1/r`.
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