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A soldier walks towards a high wall taki...

A soldier walks towards a high wall taking 120 steps per minute. When he is at a distance of 90 m from the wall he observes that echo of step coincides with the next step. The speed of sound must be

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360 m/s
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A boy standing in front of a wall at a distance of 85 m produces 2 claps per second. He notices that the sound of his clapping coincides with the echo. The echo is heard only once when clapping is stopped. Calculate the speed of sound.

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A boy is walking away from a well at a speed of 1.0 m//s in a direction at right angles to the wall. As he walks, he below a whistle steadily. An observer towards whom the boy is walking hears 4.0 beats per second. If the speed of sound is 340 m//s , what is the frequency of the whistle?

A soure of sound of frequency 165 hz is placed in front of a wall at a distance 2 m from it. A dtector is also placed in front of the wall at the same distance from it. Find the minimum distance between the source and detector for which maximum sound is recorded int he detector . the speed of sound is 330 m/s

A man is walking towards a vertical pillar in a straight path at a uniform speed. At a certain point A on the path, he observes that the angle of elevationof the top of the pillar is 30^(@) . After walking for 5(sqrt3+1) minutes from A in the same direction, at a point B, he observes that the angle of elevation of the top of the pillar is 45^(@) . Then the time taken (in minutes) by him, to reach from B to the pillar, is (take sqrt3=1.73 )

A source of sound of frequency 1000 H_(Z) moves unifornly along a straight line with velocity 0.8 times velocity of sound . An observer is located at a distance l= 250 m from this line. Find (a) the frequency of the sound at instant when the source is closest to the observer. (b) the distance of the source when he observer no change in the frequency.

AAKASH SERIES-WAVE MOTION AND SOUND-PROBLEMS (LEVEL - II)
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  2. Two sound sources are moving in opposite directions with velocities v...

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  3. A 300 Hz source, an observer and wind are moving as shown in the figur...

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  4. A person standing on a road sends a sound signal to the driver of a ca...

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  5. A stationary sound sound 's' of frequency 334 Hz and a stationary ovs...

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  6. Spherical waves are emitted from a 1.0 W source in an isotropic non-ab...

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  7. The intensity of sound from a point source is 1.0 xx 10^-8 Wm^-2, at a...

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  8. Most people interpret a 9.0 dB increase in sound intensity level as a ...

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  9. About how many times more intense will the normal ear perceiver a soun...

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  10. The explosion of a fire cracker in the air at the a heigth of 40 m pro...

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  11. The sound level at a point 5.0 m away from a point source is 40 dB. Wh...

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  12. If the intensity of sound is doubled, by how many decibels does the so...

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  13. Sound with intensity larger than 120 dB appears painful to a person. A...

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  14. Two waves, each having a frequency of 100 Hz and a wavelength of 2.0 c...

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  15. Two waves, each having a frequency of 100 Hz and a wavelength of 2.0 c...

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  16. Two waves, each having a frequency of 100 Hz and a wavelength of 2.0 c...

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  17. Three component sinusoidal waves progressing in the same directions al...

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  18. A soldier walks towards a high wall taking 120 steps per minute. When ...

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  19. A man stands before a large wall at a distance of 50.0m and claps his ...

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  20. A road runs midway between two parallel rows of buildings. A motorist ...

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