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PHY 104 Wave and sound Objective Question
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Question

An observer is moving towards a stationary sound source with speed v₀. If the source emits sound at frequency f and the speed of sound in the medium is v, what is the observed frequency f', as per the Doppler Effect formulas in the document?
Options
A <i>f' = f * (v - v₀) / v</i>
B <i>f' = f * (v + v₀) / v</i>
Correct Answer
C <i>f' = f * v / (v - v₀)</i>
D <i>f' = f * v / (v + v₀)</i>
Correct Answer

Option B is the correct answer.

Detailed Explanation

On page 16, under 'Doppler Effect', 'Case 1: Source constant, observer moving towards it', the document derives the formula for the observed frequency as f' = f + (v₀/v)f. This can be rewritten as f' = f * (1 + v₀/v) = f * (v + v₀)/v.

Hint

Look for 'Case 1: Source constant, observer moving towards it' on page 16 and the derived formula for f'.

Question Info

Course: PHY 104
Topic: Wave and sound
Type: Objective
Difficulty: Not specified
Question 336 of 947
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