(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Whistle frequency is 595 Hz for the train and sounds higher or lower depending on whether it approaches it or recedes. Calculate the difference in frequency between approaching and receding train whistle for a train moving at a speed of 105 km/h. Speed of sound is 340 m/s

2. Relevant equations

change in f = (2frequency(u/v))/(1-u^2/v^2)

3. The attempt at a solution

105 km/h = 29.16 m/s

u/v = 29.16/340 = .08578

change if f = (2frequency(.08578))/(1-.08578^2)

Ok this may sound really stupid but I saw an example of this problem worked and it used frequency as 105 km/h the speed of the train so inputted looked like this

change if f = (2(105)(.08578))/(1-.08578^2)

This makes no sense to me but I just want to make sure it SHOULDNT be this (105) for frequency since its not actually in Hz. I assume frequency would be the whistle frequency 595 Hz correct?

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# Homework Help: Train whistle frequency difference in approaching and receding

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