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Doppler Effect
• You hear the high pitch of the siren of the approaching
ambulance, and notice that its pitch drops suddenly as the
ambulance passes you. That is called the Doppler effect.
Doppler Effect
• (f1-f0)/f0 ≅ V/v
a) +V for approach,
b) −V for separation
A girl is sitting near the open window of a train that is
moving at a speed of 10 m/s. The girl’s uncle stands
near the tracks and watches the train move away. The
girl’s brother also stands near the tracks but ahead of the
train, and watches the train getting closer. The train is
blowing a whistle with a frequency of 500 Hz. What
frequency does the girl hear? Her uncle? Her brother?
Shock Wave
Sonic Boom
Interference
Wave interference is the phenomenon which occurs
when two waves meet while traveling along the same
medium.
The interference of waves causes the medium to take on
a shape which results from the net effect of the two
individual waves upon the particles of the medium.
