Finding the speed of an approaching object using the doppler effect and sonar

AI Thread Summary
The discussion focuses on using the Doppler effect and sonar to calculate the speed of an approaching object. The main confusion arises from understanding the "double shift" in frequency, questioning whether to apply a single percentage change or to use two separate functions for the frequency shifts. Participants suggest breaking the problem into two steps, as hinted, to clarify the calculations. The importance of correctly applying the Doppler effect formulas is emphasized for accurate results. The conversation ultimately aims to resolve the complexities of frequency shifts in the context of the problem.
jellyman
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Homework Statement


I attatched 2 images, the problem, and my work (including the formula needed)This "double shift" is what's getting me. Is it going 2% towards the object, and 2% from it?

Or I'm I suppose to use 2 functions:F'=(f+xf) and F'=(f+yf) where x + y = 0.04?

Homework Equations


See pic.

The Attempt at a Solution


See pic.
 

Attachments

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Do as the hint suggests - in two steps.
 

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