10) Cars Go VROOM!

     Today after working all day at Subway in Pearl Ridge Uptown, I came home and sat outside on a chair exhausted and relieved to finally relax.  Today was a very busy day for us at Subway since the inspector came today to check everything at the store.  As of right now I don't feel so good, but anyways, sitting down feels awesome.  As I removed my shoes, I watched and listened as the cars drove by.  I noticed as the cars were coming closer in my vision that the sound each car made was different from the sound that each car made after each one passed me. This simple observation can be explained by an Austrian physicist named Christian Doppler.  His idea is called the Doppler Effect, which is a change in the frequency of a wave due to motion of the source and/or the listener.  There are three equations that are based on a moving and listening source.  In my case, I am the listener and the car(s) are the moving source(s).  In order to solve for any of the terms, such as the frequency of the moving listener or source or even the stationary listener or mover, I would have to use the equations that Christian Doppler came up with.  Below is a video of a few cars displaying the Doppler Effect.