In presence of a resonant body, the sound produced by a body is intensified, is the principle of conservation of energy violated here?

In presence of a resonant body, the sound produced by a body is intens

1.	In presence of a resonant body, the sound produced by a body is intensified, is the principle of conservation of energy violated here?
Answer» Solution :The principle of conservation of energy is not violated here. Suppose, a tuning fork is set into vibration. The loudness of the sound so produced is not very large. If the vibrating fork is held on a hollow wooden box, the sound is Intensified. in this CASE the air inside the box acts as a resonant body. But it is found that the sound of the tuning fork lasts for a long time in the first case. But in the SECOND case, the sound of the tuning fork is SHORT-lived. The total dissipation of energy In both the cases is the same. In the first case, the rate of dissipation of energy is low but continues for a long time. But in the second case, the rate of dissipation of the. same amount of energy is comparatively high and therefore the sound DIES down in a short time. it does not violate the principle of conservation of energy.