Sound Waves
Trending Questions
Why sound cannot travel through the vacuum (or through outer space)?
How does sound travel in air?
What is a vibratory motion? Explain with examples.
How can you show that sound cannot travel through a vacuum? Draw a labelled diagram of the apparatus used.
- Air
- Vacuum
- Water
- Solids
How do sound waves travel in air medium? Explain.
Lightning and thunder take place in the sky at the same time and at the same distance from us. Lightning is seen earlier and thunder is heard later. Can you explain why?
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?
Explain why, the flash of lightning is seen first but the sound of thunder is heard a little later (though lightning and thunder take place in the sky at the same time and same distance from us).
Name the substance which vibrates in a flute to produce sound.
Sound waves can travel through:
True
False
- Water
- Vacuum
- rarefaction
- trough
- compression
A sound wave is a pressure wave; regions of high pressure (compressions) and low pressure (rarefactions) are established as the result of the vibrations of the sound source. These compressions and rarefactions result because the sound
is more dense than air and thus has more inertia, causing the bunching up of sound
waves have a speed which is dependent only upon the properties of the medium
is like all waves, it is able to bend into the regions of space behind obstacles
is able to reflect off fixed ends and interfere with incident waves vibrates longitudinally, the longitudinal movement of air produces pressure fluctuations
How does a sound making object differ from one that is silent?
(a) Why a sound cannot be heard on the moon
(b) How do astronauts talk to one another on the surface of moon and why ?
- transverse
- longitudinal
- non-mechanical
If you want to hear a train approaching from far away, why is it more convenient to put the ear to the track?
Can we talk in the moon as on earth? If, not how astronauts can communicate with each other at moon?
How is sound produced ?
- The amplitude of sound made by the bell decreases with time.
- The frequency of the sound made by the bell increases with time.
- Sound waves need a material medium to travel through.
- The sound waves from the bell become transverse.
Why does a vibrating simple pendulum not produce any sound?
Shrillness
pitch
(a) State two methods of producing sound.
(b) How does sound from a sound producing body travel through air to reach our ears ?
Name one solid, one liquid and one gas through which sound can travel.
The sound waves travel fastest :
(a) in solids (b) in liquids (c) in gases (d) in vacuum
Boojho saw a cracker burst at night at a distance from his house. He heard the sound of the cracker a little later after seeing the cracker burst. Give the reason for the delay in hearing the sound.
