Answer
This is a hands-on demonstration. Try this with your friends, and be prepared to explain the physics of the demonstration to them.
Work Step by Step
You should hear that the sound is louder when both the sound source and your ears are underwater.
When you slide back and forth in the tub in time with the natural frequency of the sloshing water, the resonance will cause a large-amplitude response, and the result may be a wet bathroom floor!
