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प्रश्न
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उत्तर
Bats make a series of twittering sound, so high pitched that human ear can not hear. These sound waves strike against the obstacles less in their path of flight and send back echoes to the bat’s ear. The echoes tell the bats, how they must turn in the air to avoid colliding with the obstacles or with one another.
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संबंधित प्रश्न
What is loudness of sound? What factors does it depend on?
Fill in the blank.
The pitch of a sound depends on its ________.
How is it possible to recognize a person by his voice without seeing him?
What are wavelength, frequency, time period and amplitude of a sound wave?
In fig. shows a snap shot of a wave from of frequency 50 Hz in a string. The numbers in the diagram represents distance in centimeters. Fpr the wave motion, find
(a) Wavelength,
(b) Amplitude,
(c) Velocity.
What is sound? How is it produced?
Describe a simple experiment to determine the speed of sound in air. What approximation is made in the method described by you?
An observer sitting in line of two tanks watches the flashes of two tanks firing at each other at the same time, but he hears the sounds of two shots 2s and 3.5s after seeing the flashes. If distance between the two tanks is 510m, find the speed of sound.
A cannon is fired at A (see diagram). An observer at B hears two sounds. The first sound is heard after 1 second and the second 3s after the observer sees the flash. (Velocity of sound = 340 ms−1)
(i) Why does the observer see the flash before he hears the sound?
(ii) Calculate the distance x between the observer and the wall.
Select the correct option:
A part of the longitudinal wave in which particles of the medium are closer than the normal particles is called:
A continuous disturbance is created on the surface of water in a ripple tank with a small piece of cork floating on it. Describe the motion of the cork. What does the motion of the cork tell about the disturbance?
Is sound a form of energy?
Can you hear the sound produced due to the vibrations of second's pendulum?
What type of sound is produced by elephants and whales?
Match the following.
| 1. | Tuning fork | The point where density of air is maximum |
| 2. | Sound | Maximum displacement from the equilibrium position. |
| 3. | Compressions | The sound whose frequency is greater than 20,000 Hz. |
| 4. | Amplitude | Longitudinal wave. |
| 5. | Ultasonics | Production of sound. |
Waves created by Earth Quake are Infrasonic.
What is a longitudinal wave?
What are the uses of infrasonic sound?
