
214 Classical Mechanics
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A heavily damped system loses its energy rapidly, and its Q is low. For a lightly damped
oscillator, Q ≅ ω
0
/2β and is much greater than 1. A tuning fork has a Q of a thousand or so;
an undamped oscillator has innite Q.
In summary, light damping slightly reduces the frequency of an oscillator and intro-
duces a decay factor exp(–βt) in the amplitude. The average energy also decays exponen-
tially, losing a fraction of its value per unit of time.
Example 7.2
A musician’s tuning fork rings at A above middle C, 440 Hz. A sound-level meter indicates that
the sound intensity decreases by a ...