Physics
A boy tunes a radio channel to a radio station 93.5 MHz.
(a) Name and define the scientific wave phenomenon involved in tuning the radio channel.
(b) Name the important characteristics of sound that is affected during this phenomenon.
(c) Convert 93.5 MHz to SI unit.
Answer
(a) Resonance
Definition — When the frequency of the externally applied periodic force on a body is equal to its natural frequency, the body readily begins to vibrate with an increased amplitude. This phenomenon is known as resonance.
(b) Loudness, when resonance occurs the loudness increases as the amplitude of the vibration is increased.
(c) 1 MHz = 106 Hz
93.5 MHz = 93.5 x 106 Hz = 9.35 x 107 Hz
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