CBSE-XI-Physics
17: Light Waves
- #7An amplitude modulated (AM) radio wave bends appreciably round the corners of a 1 m × 1 m board but a frequency modulated (FM) wave only bends negligibly. If the average wavelengths of the AM and FM waves are
λa and λf,
(a)
λa>λf
(b)
λa=λf
(c)
λa<λf
(d) We don’t have sufficient information to evaluate the relation of
λa and λf.digAnsr: aAns : (a) `` {\lambda }_{a}>{\lambda }_{f}``
An electromagnetic wave bends round the corners of an obstacle if the size of the obstacle is comparable to the wavelength of the wave. An AM wave has less frequency than an FM wave. So, an AM wave has a higher wavelength than an FM wave and it bends round the corners of a 1 m `` \times `` 1m board.
λ
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