Question

Someone on the deck of a pool is playing a guitar while you are underwater. How does the sound wave differ after it enters the water when you hear it as compared to the sound wave before entering the water? Include as many variables as possible in your explanation (velocity, frequency, wavelength, amplitude, energy, direction, period). Please explain fully.

I am confused since I know waves move faster in a less dense medium. However, water is denser than air, but sound waves move faster in water?

Answer 1

You really need to understand the difference between other waves and sound waves .

Sound waves exist only because of vibrations between particles in a medium. If there is no vibration, there will be no sound.

Water is denser than air means particles in water are closely spaced so they can quickly transmit vibration energy from one particle to the next, this is the reason sound waves travel much faster in water ( around 4 times faster) than in air !!

I hope that you understand the concept now.

Now,

when sound waves travel in the water from air, energy with which the sound was made is same, this means frequency remains constant , so wavelength has to increase to maintain the speed

As period depends on frequency, so, if frequency is same, period will also be same