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प्रश्न
An electromagnetic wave has a time period of 4 × 10-8 s. Calculate its frequency in MHz.
उत्तर
Time period = T = 4 × 10-8 s
Frequency of sound = ƒ =?
f = `1/"T"`
f = `1/(4xx10^-8) = 0.25 xx 10^8` Hz
f = 25 × 106 Hz
f = 25 MHz
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