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प्रश्न
A plane electromagnetic wave travels in vacuum along z-direction. What can you say about the directions of its electric and magnetic field vectors? If the frequency of the wave is 30 MHz, what is its wavelength?
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उत्तर
The electromagnetic wave travels in a vacuum along the z-direction. The electric field (E) and the magnetic field (H) are in the x-y plane and mutually perpendicular.
Frequency of the wave, v = 30 MHz = 30 × 106 s−1
Speed of light in a vacuum, c = 3 × 108 m/s
Wavelength of a wave is given as:
`lambda = "c"/"v"`
= `(3 xx 10^8)/(30 xx 10^6)`
= 10 m
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