In physics class the other day, we learned about the Doppler effect which, at first, I immediately thought of the news when the weatherman talks about their technology. Mr. Fullerton then told us that the Doppler effect can be applied in other situations as well. The Doppler effect is a shift in wave's observed frequency due to relative motion between the source of the wave and the observer of the wave. When told what the Doppler effect is I thought of the time I went to the St. Patty's Day Parade and heard all of the cars honk their horns. As I stood in the same spot the whole time, the vehicle would approach me and it sounded as though the car's horn was much louder than it was when it was coming towards me, and once again as it drove away from me, I seemed to hear a lower pitch. In reality, this is simply the Doppler effect in motion as the waves have a fixed speed in a given medium and as waves are emitted, the moving car makes the observer (me) encounter wave fronts at shifting frequencies. So although the car sounds as thought the pitch is getting much higher, it really stays the same which is explained by the Doppler effect.