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Question
What is the wavelength of the wave whose frequency is 1012 Hz? Name the electromagnetic wave.
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Solution
Frequency of the wave = 1012 Hz.
Velocity of electromagnetic wave = 3 × 108 m/sec.
∴ Wavelength of the wave = `"v"/"f"=(3xx10^8)/10^12`
= 3 × 10−4 m
= 3 × 10−2 cm.
These waves are heat waves or infra-red waves whose wavelength varies from 10−2 to 10−4 cm.
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