Doppler Effect
A loud speaker tuned to a single frequency, f0, is rotating in a circle with speed v. For each of the following statements select the correct option.
• The frequency heard by the observer when the speaker is at A is greater than f0.
• If the speed of rotation is increased while the speaker is at D, the frequency heard by the observer is equal to f0.
• The frequency heard by the observer when the speaker is at B is less than f0.
• The frequency heard by the observer when the speaker is at C is greater than f0.
• The frequency heard by the observer when the speaker is at D is equal to f0.
• The frequency heard by the observer when the speaker is at A is greater than f0.
• If the speed of rotation is increased while the speaker is at D, the frequency heard by the observer is equal to f0.
• The frequency heard by the observer when the speaker is at B is less than f0.
• The frequency heard by the observer when the speaker is at C is greater than f0.
• The frequency heard by the observer when the speaker is at D is equal to f0.