Music is amazing and surrounds us everyday. At first it may not seem like physics is in music because come on, it's music. But because physics is well...everything...it has to be in music. Because music is sound you just have to look at the physics of sound.
When you're blasting your music and you can feel the bass as its playing you're experiencing sound waves. These aren't your usual waves,this are compressional waves in which you cant see. If you've done certain math classes you may remember that there is more to compressional waves. These waves have a frequency to them which is how many times the waves go past a point and in a certain amount of time. Sometimes these waves are really short while others are really long! The short vs long is the wave length between the tops of the waves. And while the length between them can change, so can the height. The height of the wave is just referred to as the amplitude or an amp. When plugging your guitar into your amp, your amp just makes bigger sound waves increasing the sound that comes out so people can actually hear what you're playing.