When an ambulance with a blaring siren moves towards an observer, the pitch of the siren appears to be higher. This is due to: MCQ with Answer and Explanation

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When an ambulance with a blaring siren moves towards an observer, the pitch of the siren appears to be higher. This is due to:

A. Acoustic resonance

B. The Doppler Effect

C. Interference of sound waves

D. Reverberation

Answer: Option B

Solution (By JKExamLibrary)

The Doppler Effect is the apparent change in the frequency (and thus pitch) of a wave due to the relative motion between the source and the observer. As the ambulance approaches, sound waves get compressed, increasing the perceived frequency (higher pitch). As it moves away, waves stretch, lowering the frequency.

This question belongs to: Science Physics

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C. Zero

D. Variable

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Correct Answer: Option C

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What is the primary function of a rectifier in an electrical circuit?

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Correct Answer: Option A

Explanation:
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