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When is echo heard?...

When is echo heard?

A

If the time interval between original sound and reflected sound must be atleast 0.1s.

B

If the time interval between original sound and reflected sound is less than 0.1 s.

C

If the time interval between original sound and reflected sound is less than 0.01 s.

D

If the time interval between original sound and reflected sound is only 0.01 s.

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If the time-interval between originsl sound and reflected sound must be atleast 0.1 s.
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KUMAR PRAKASHAN-SOUND-QUESTIONS AND ANSWERS (Choose the correct option from those given below cach question:)
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  2. Sound of which frequency from the following is ultrasonic sound?

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  3. When is echo heard?

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  4. Which of the following relations is true for sound waves?

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  6. What is the phase difference between consecutive crest and through ?

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  7. The distance between two consecutive conden sations in the sound wave ...

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  8. In the air, the velocity of sound wave is 340 ms^(-1) and wavelength i...

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  9. Waves of light are ........

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  10. On which of the following factors does the velocity of wave not depend...

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  11. The wavelength of the wave produced on the surface of water is 2 cm. I...

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  12. Two waves produced from a source are shown in the following figure. St...

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  14. What is the frequency range of audible sound wave?

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  15. Which type of sound waves does the bat produce?

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  16. Who can experience ultrasonic sound?

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  17. Which waves are used in ECG technique?

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  18. Whose unit is decibel (dB)?

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  19. The SI unit of intensity of sound is ........

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  20. Note is a sound which is ........

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