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प्रश्न
The incidence of ______ in daily life shows that the velocity of sound is less than the velocity of light.
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उत्तर
The incidence of thunderstorms in daily life shows that the velocity of sound is less than the velocity of light.
Explanation:
In a thunderstorm, we see the flash of lightning before we hear the sound of thunder. This happens because light travels much faster than sound. Light reaches our eyes almost instantly, while sound takes more time to reach our ears. Therefore, thunderstorms show that the velocity of sound is less than the velocity of light.
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संबंधित प्रश्न
Describe an experiment to show that sound can travel in water.
Describe an experiment to show that sound can travel in a solid.
A boy fires a gun and another boy at a distance of 1020 m hears the sound of firing the gun 3 s after seeing its smoke. Find the speed of sound.
Which of the following is the speed of sound in copper and which in aluminium?
(a) 5100 m/s
(b) 1500 m/s
(c) 3750 m/s
What name is given to those aircrafts which fly at speeds greater than the speed of sound?
What is meant by supersonic speed?
A sound signal of 128 vibrations per second has a wavelength of 2.7 m. Calculate the speed with which the wave travels.
When we put our ear to a railway line, we can hear the sound of an approaching train even when the train is far off but its sound cannot be heard through the air. Why?
The speeds of sound in four different media are given below. Which of the following is the most likely speed in m/s with which the two under water whales in a sea talk to each other when separated by a large distance?
The drawing shows a ship 800 m from a cliff. A gun is fixed on the ship. After 5 seconds the people at the front of the ship hear the sound of the gun again.
(a) What is the name of this effect ?
(b) What happens to the sound at the cliff ?
(c) How far does the sound travel in 5 seconds ?
(d) Calculate the speed of sound.
Fill in the blank and explain.
The velocity of sound in steel is ______ than the velocity of sound in water.
The velocity of sound in solid is ______ than the velocity of sound in air.
The velocity of sound in air at a particular temperature is 330 ms–1. What will be its value when temperature is doubled and the pressure is halved?
Velocity of sound in the atmosphere of a planet is 500 ms–1. The minimum distance between the sources of sound and the obstacle to hear the echo should be
The thunder of cloud is heard 9.8 seconds later than the flash of lightning. If the speed of sound in air is 330 ms–1, what will be the height of the cloud?
Establish the relationship between the speed of sound, its wavelength and frequency. If the velocity of sound in air is 340 m s–1, calculate
(i) wavelength when the frequency is 256 Hz.
(ii) frequency when the wavelength is 0.85 m
When temperature increases the speed of sound ______.
On which factors does the speed of sound in the gaseous medium depend?
Numerical problems:
Two persons are at opposite ends of a steel rod. One strikes the end of the rod with a stone. Find the ratio of time taken by the sound wave in the air and in steel to reach the second person. (Sound of speed in steel = 5960 ms-1, Sound of speed in air = 344 ms-1).
