Doppler frequency for receding observer
An observer moves away from a stationary sound source in a standing-wave string practical. The source frequency is \(625\,\text{Hz}\), sound speed is \(340\,\text{m s}^{-1}\), and observer speed is \(17\,\text{m s}^{-1}\). Calculate the observed frequency. Use the diagram labels before calculating the requested value. Enter the numerical result and choose the interpretation that matches the wave physics.
Worked practice: physics data and result
Read the physical quantities first, then calculate the result and state what it means.
Write a full answer
Now write the response in full, in your own words — this is what the exam asks for. The AI marks it on the same moves you built above (focus, evidence, technique, judgement) and gives feedback on reasoning, evidence, and expression.