Concept explainers
(a)
Wavelengths of AM and FM signals.
(a)
Answer to Problem 31QP
Wavelength of AM is
Explanation of Solution
Write the relation between speed of signal, frequency of signal and wavelength of signal.
Here,
For AM, the frequency of the signal received by radio is given as
For AM, the frequency of the signal received by radio is given as
Conclusion:
Substituting
For FM,
Therefore, wavelength of AM is
(b)
Whether AM or FM broadcast in higher frequencies.
(b)
Answer to Problem 31QP
The FM broadcast in higher frequencies.
Explanation of Solution
The frequency of the AM radio waves produced by the radio station is given as
By comparing the value of frequency of AM and FM, the FM broadcast in higher frequency than the AM. Due to this reason FM is better than the AM. FM can travel more distances than AM due to less dissipation than AM.
Conclusion:
Therefore, the FM radio signal has more frequency.
(c)
The photon energies of AM and FM.
(c)
Answer to Problem 31QP
The photon energy of AM is and photon energy of FM is
Explanation of Solution
Write the relation between photon energy and frequency.
Here,
For AM, the frequency of the signal received by radio is given as
For AM, the frequency of the signal received by radio is given as
Conclusion:
Substituting
For FM,
Therefore, photon energies of AM is
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Chapter 5 Solutions
21st Century Astronomy
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