A person is listening to a tone of 500 Hz sitting at a distance of 450 m from the source of the sound. What is the time interval between successive compressions from the source?

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Chapter 11

NCERT

Class 9

Science

Solutions

4. A person is listening to a tone of 500 Hz sitting at a distance of 450 m from the source of the sound. What is the time interval between successive compressions from the source?

Question:

A person is listening to a tone of 500 Hz sitting at a distance of 450 m from the source of the sound. What is the time interval between successive compressions from the source?

Answer:

Frequency v = 500 Hz

and distance d = 450 m

Time period T = 1/v

T = 1/500

T = 0.002 s

‍

Note: [The time taken or time period T between consecutive compression does not depend on the position of the object (distance d = 450 m), it is given to confuse only so that the skill of the students can be accurately tested.]

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