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ELECTROMAGNETIC WAVES — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsELECTROMAGNETIC WAVES2 Marks
Question
Write a short note on radio waves.
✓

Answer

→Radio waves are produced by the accelerated motion of charges in conducting wires.
→They are used in radio and television communication systems.
→Frequency range: from 500 kHz to about 1000 MHz.
→Range of frequencies for different bands:
(i) AM (Amplitude Modulated) band: from 530 kHz to 1710 kHz
(ii) SW band: Up to 54 MHz
(iii) TV waves band: 54 MHz to 890 MHz
(iv) FM (Frequency Modulated) radio band: 88 MHz to 108 MHz
(v) UHF (Ultra High Frequency band: 300 MHz to 3000 MHz.

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