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प्रश्न
Solve the numerical problem.
Calculate the frequency in MHz of a radio wave of wavelength 250 m. Remember that the speed of all EM waves in a vacuum is 3.0 × 108 m/s.
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उत्तर
Given: λ = 250 m, c = 3 × 108 m/s
To find: Frequency (ν)
Formula: c = νλ
Calculation: From formula,
ν = `"c"/λ=(3xx10^8)/250` = 1.2 × 106 Hz = 1.2 MHz
The frequency of a radio wave is 1.2 MHz.
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