Question
train is approaching the station at a speed of 20m.s sounds a 220 hz horn. What frequency does an observer on the station platform hear
Answers
drwls
Frequency is shifted upward by
fo * (V/a)
fo = 220 Hz
a = speed of sound = 340 m/s
V = 20 m/s
f = fo*[1 + (V/a)]
There is a more accurate Doppler shift formula, but this is accurate enough when a<<c, as is the case here.
For the exact formula, see
http://en.wikipedia.org/wiki/Doppler_effect
fo * (V/a)
fo = 220 Hz
a = speed of sound = 340 m/s
V = 20 m/s
f = fo*[1 + (V/a)]
There is a more accurate Doppler shift formula, but this is accurate enough when a<<c, as is the case here.
For the exact formula, see
http://en.wikipedia.org/wiki/Doppler_effect