Sound
What is sound?
Sound is energy, it is caused by the vibration of particles and that is why it
needs a medium.
I will explain this via an analogy
You have put your hand in some water now when u shake your hand the
water starts moving and splashes against its surroundings. But if there was no
water then there would be no splash.
In this case water is the medium,
the splash is the sound created and your hand can be the cause of the medium
to vibrate.
From this we see that if there is no medium then their cannot be any sound
as sound is created by particles vibrating if their are no particles then their
cannot be any sound. That is why if we stand in a vacuum
(assuming you can breathe without any apparatus) and scream no sound will
be heard, this is because there is no medium present.
hence we can conclude that sound needs a medium to propagate.
Sound is energy, it is caused by the vibration of particles and that is why it
needs a medium.
I will explain this via an analogy
You have put your hand in some water now when u shake your hand the
water starts moving and splashes against its surroundings. But if there was no
water then there would be no splash.
In this case water is the medium,
the splash is the sound created and your hand can be the cause of the medium
to vibrate.
From this we see that if there is no medium then their cannot be any sound
as sound is created by particles vibrating if their are no particles then their
cannot be any sound. That is why if we stand in a vacuum
(assuming you can breathe without any apparatus) and scream no sound will
be heard, this is because there is no medium present.
hence we can conclude that sound needs a medium to propagate.
How does sound propagate?
Sound propagates in 2 ways:
Longitudinal Waves: Sound is created by a vibrating object. The object will move forward and backward. When the object moves forward it compresses the medium in this case air in front of it, this layer of air is called a compression, after this the object moves backwards, this causes a the medium to get expanded this area is called a rarefaction. As a Longitudinal wave sound travels in compressions and rarefactions.
Transversal Waves: In Transversal Waves the particles of the medium vibrate in an up down motion whereas the wave moves in a horizontal manner.
Longitudinal Waves: Sound is created by a vibrating object. The object will move forward and backward. When the object moves forward it compresses the medium in this case air in front of it, this layer of air is called a compression, after this the object moves backwards, this causes a the medium to get expanded this area is called a rarefaction. As a Longitudinal wave sound travels in compressions and rarefactions.
Transversal Waves: In Transversal Waves the particles of the medium vibrate in an up down motion whereas the wave moves in a horizontal manner.