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प्रश्न
Write a short note on the radio waves.
उत्तर
It is produced by oscillators in electric circuits. The wavelength range is 1 x 10-1 m to 1 x 104 m and the frequency range is 3 x 109 Hz to 3 x 104 Hz. It obeys reflection and diffraction. It is used in radio and television communication systems and also in cellular phones to transmit voice communication in the ultrahigh-frequency band.
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