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What is an echo?
What is reverberation?
What is SONAR?
Sound is produced by a vibrating source. Why then a vibrating pendulum does not produce any sound?
What is the audible range for a normal human being?
Give Reasons for the Following:
Why sound waves are called mechanical waves?
Why are ceilings of concert halls curved?
Why sound wave is called a longitudinal wave?
Why echoes can’t be heard in a small room?
Why echoes in the long gallery and big halls can be heard?
Transverse waves and longitudinal waves.
Crest and trough.
Infrasonic vibrations and ultrasonic vibrations.
Compression and rarefaction.
Loudness and intensity of sound.
With the help of a labelled diagram, explain the working of the human ear.
Illustrate with the help of an experiment that sound requires a medium to propagate.
A sound wave of length 70 cm travels 840 m in 25 seconds. What is the velocity and frequency of sound?
An echo is heard after 0.8 seconds, when a person fires a cracker 132.8 m from a high buildings. Calculate the speed of sound.
A source of wave produces, 40 crests and 40 troughs in 0.4 seconds. Find the frequency of the wave.
Why an echo is not heard when distance between source of sound and reflecting body is 10 m?
The distance between the crest and trough of a transverse wave is 15 cm, what is the velocity of the wave if its frequency is 1000 Hz?
Two astronauts cannot hear each other on the moon. Why?
Sometimes our dog beings to bark without any reason. Can you explain, why?
In which case is the speed of sound more; the humming of a bee or the roaring of a lion?
When is the velocity of sound more; during winters or during summers?
Can elephants hear frequencies less than 20 Hz?
Which of the following are transferred from one place to another place by the waves?
Sound waves are:
On a slinky we can produce:
The distance between consecutive crests is:
Hertz is a unit of :
If the density of a medium through which sound is propagation is minimum, then this point is called:
The audible range for a normal human being is:
Ultrasonic are not used in:
A bomb explodes on the Moon, How long will the sound of explosion take to reach the Earth?
The walls of a hall built for musical concert should :
In an orchestra, the musical sounds of different instruments are distinguished from one another by the characteristic of:
The bells of a temple are made of large size. It is for:
An astronaut cannot hear his companion on the surface of the Moon because:
The loudness of a sound depends upon:
In the bell jar experiment, as air is removed from the jar:
Write true of false for the following statements:
Sound waves are transverse whereas light waves are longitudinal in nature.
Distance between a crest and the next trough in a wave motion is λ/4.
The audible range of frequencies is 20 Hz-20 KHz.
The frequency of a sounding body of time period 0.01 sec is 100 Hz.
The minimum distance between a source and the reflector of sound should be 34 m.
Sound waves travel faster in air than in water.
Sound travels faster at a higher temperature than at a lower
temperature.
Sound and light travel in a medium in the form of crests and troughs and rarefactions and compressions respectively.
Light waves require no medium for their propagation.
Sound produced by a sounding body of frequency 300 Hz covers 34 m in the time the sounding body produces 30 vibrations.
Velocity of sound in air is more for higher frequency than for lower frequency.
The wavelength of 5 MHz ultrasound in a medium where the velocity is 1540 m s-1 is 0.3 mm.
