A sound is produced on the mouth of a bell if the depth of the bell is 200 m. find out time when eco comes back... given speed of light=350m/sec
plz tell correct answer with solution
Answers
Answer:
uestion 1
How does the sound produce by a vibrating object in a medium reach your ear?
Answer
When an object vibrates, it vibrates the neighboring particles of the medium. These vibrating particles then vibrate to the adjacent particles After displacing the adjacent particle the first particle of medium comes back in its original position. This process continues in the medium till the sound reaches your ear.
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Question 2
Explain how sound is produced by your school bell.
Answer
When the bell continues to move forward and backward, it creates a series of compressions and rarefactions making production of sound.
Question 3
Why are sound waves called mechanical waves?
Answer
Sound waves needs material medium to propagate therefore, they are called mechanical waves.Sound waves propagate through a medium because of the interaction of the particles present in that medium.
Question 4
Suppose you and your friend are on the moon. Will you be able to hear any sound produced by your friend?
Answer
Sound waves needs a medium through which they can propagate. Since there is no material medium on the moon due to absence of atmosphere, you cannot hear any sound on the moon.
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Question 5
Which wave property determines (a) loudness, (b) pitch?
Answer
(a) Loudness is determined by Amplitude. The amplitude of a sound directly proportional to amplitude of wave. If the amplitude of a sound is large, then the sound produced will also be loud
(b) pitch is determined by Frequency. The pitch of a sound is proportional to its frequency. High pitched sounds have high frequency
Question 6
Guess which sound has a higher pitch: guitar or car horn?
Answer
Guitar has a higher pitch than car horn, because sound produced by the strings of guitar has high frequency than that of car horn. High the frequency higher is the pitch.
Question 7
What are wavelength, frequency, time period and amplitude of a sound wave?
Answer
Wavelength
The distance between two consecutive compressions or two consecutive rarefactions is known as the wavelength. Its SI unit is metre (m).
Frequency
The number of complete oscillations per second is known as the frequency of a sound wave. It is measured in hertz (Hz).
Amplitude
The maximum height reached by the crest or trough of a sound wave is called its amplitude.
Question 8
How are the wavelength and frequency of a sound wave related to its speed?
Answer
Speed, wavelength, and frequency of a sound wave are related by the following equation:
Speed (v) = Wavelength (λ) × Frequency (ν)
v =λ × ν
Question 9
Calculate the wavelength of a sound wave whose frequency is 220 Hz and speed is 440 m/s in a given medium.
Answer
Given in the question
Frequency of the sound wave(ν)= 220 Hz
Speed of the sound wave(v)= 440 m s-1
For a sound wave,
Speed (v) = Wavelength (λ) × frequency (ν)
v =λ × ν
or λ=v/ ν = 440 / 220 = 2m
So the wavelength of the sound wave is 2 m.
Question 10
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
The time interval between two successive compressions is equal to the time period of the wave. This time period is reciprocal of the frequency of the wave and is given by the relation
T= 1 / Frequency = 1/ 500 = 0.002 s