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Physics Ncert Solutions Class 12th Physics Class 12th Electromagnetic Waves

8.5 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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Payal Gupta | Contributor-Level 10

3 months ago

8.5 The lowest tuning frequency $ν_{1}$ = 7.5 MHz = 7.5 $\times 10^{6}$ Hz

The highest tuning frequency $ν_{2}$ = 12 MHz = 12 $\times 10^{6}$ Hz

Speed of light, c = 3 $\times 10^{8}$ m/s

The wavelength for lowest tuning frequency, $λ_{1}$ = $\frac{c}{ν_{1}}$ = $\frac{3 \times 10^{8}}{7.5 \times 10^{6}}$ = 40 m

The wavelength for highest tuning frequency, $λ_{2}$ = $\frac{c}{ν_{2}}$ = $\frac{3 \times 10^{8}}{12 \times 10^{6}}$ = 25 m

The wavelength of the band is 40m to 25 m

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8.5 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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