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Question
An electromagnetic wave has a time period of 4 × 10-8 s. Calculate its frequency in MHz.
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Solution
Time period = T = 4 × 10-8 s
Frequency of sound = ƒ =?
f = `1/"T"`
f = `1/(4xx10^-8)`
= 0.25 × 108 = 2.5 × 107 Hz
Convert Hz to MHz
1 MHz = 106 Hz
`f = (2.5 xx 10^7)/10^6`
= 25 MHz
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