How Does the Doppler Effect Alter Perceived Siren Frequencies at a Junction?

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The discussion focuses on calculating the maximum and minimum frequencies of a train's siren heard by a car driver at a junction, given the train's speed of 35 m/s and a siren frequency of 100 Hz. The velocity of sound is stated as 343 m/s. Key variables include the speed of sound (v), the speed of the receiver (vr), the speed of the source (vs), the original frequency (f), and the observed frequency (fo). Participants seek clarification on these variables to solve the problem effectively. Understanding the Doppler Effect is crucial for determining how the frequency changes as the train approaches and passes the stationary car.
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Homework Statement


A car stops at 50m to a road-railway junction. A train is moving with a constant velocity 35m/s towards the junction. If the train emits a siren at a frequency of 100Hz, calculate the maximum and the minimum frequency that can be heard by the car driver.

velocity of sound: 343m/s


Homework Equations


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The Attempt at a Solution


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Do you know what v, vr, vs, f, fo mean?

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