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Question
A radio can tune in to any station in the 7.5 MHz to 12 MHz band. What is the corresponding wavelength band?
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Solution
A radio can tune to minimum frequency, v1 = 7.5 MHz = 7.5 × 106 Hz
Maximum frequency, v2 = 12 MHz = 12 × 106 Hz
Speed of light, c = 3 × 108 m/s
Corresponding wavelength for v1 can be calculated as:
`lambda_1 = "c"/"v"_1`
= `(3 xx 10^8)/(7.5 xx 10^6)`
= 40 m
Corresponding wavelength for v2 can be calculated as:
`lambda_2 = "c"/"v"_2`
= `(3 xx 10^8)/(12 xx 10^6)`
= 25 m
Thus, the wavelength band of the radio is 40 m to 25 m.
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