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) Now what is the frequency of the channel? Convert this frequency into 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) Frequency of the channel is 93.5 MHz.
The SI unit for frequency is the hertz (Hz)
1 MHz = 106 Hz
93.5 MHz = 93.5 x 106 Hz
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