blossom asked in Science & MathematicsPhysics · 9 years ago

# physics pls help...propagation of sound?

hi. im studying in 9th std. im from india. i have to take physics class about" propagation of sound " tomorrow. i want some simple details about that. (i have to explain that). (which is easy to understand) i want some examples and some question and answers. pls help.. thanks

Update:

how does sound propagate...?

Update 2:

i dont have any books about sound and i searched on wikipedia , its not that much clear.

Relevance
• 9 years ago

these are some simple points related to sound

1.sound is a form of energy

2.it causes sensation of hearing on reaching the ear

3.any vibrating body could be a source of sound

4.sound needs a medium to propagate

sound cannot travel in vacuum.that is why we cannot hear anything in space as there is no medium

5.sound can be classified into 3 types based on its frequency

frequency is the no. of waves that cross a point in 1sec.foe ex:if 200waves cross a point in 1 sec the frequency of the sound is 200Hz [hertz , unit of frequency ]

6.audible ,sound freq range 20-20,000Hz

ultrasonic , freq above 20,000Hz

infrasonic , freq below 20Hz

• Anov
Lv 6
9 years ago

Sound wave is called longitudinal wave because it travels longitudinally in the direction to the propagation of the wave.It is a mechanical wave. To produce sound wave there needs a disturbance.

Like you see the waves in the river or in the sea which is due to the air flowing at its surface or due to the internal disturbance.So to say, when there is a cause there is an effect. Here Air or internal disturbance is the cause and the effect is the wave.Similarly when you strike, for example, strike a metal pie at its one end and you hear the sound at its other end very easily.The travelling mode of these waves are longitudinal.To make still more, take a piece of wood of which the mid part of it is vertically slit.Pass a long piece of thread through this slit.Hold the one end of the string and the other end also some body to hold it. Now get somebody to hold the slit- wood vertically.The string has to be reasonably taut .Now either of one of who is holding the string can move his hand up & down so that the string(Thread) starts moving up and down.Now you will see the vibration of the string with waves travelling through the slit longitudinally.Similar is the case with sound wave. I think the example makes you clear how does sound wave propagate.Thank You for your question.Note: Sound needs medium to travel.It cannot travel in vacuum.

Source(s): Do the experiment as mentioned above, or similar experiment. You can study any book relating to Basics of sound at the library.
• Anonymous
9 years ago

sound is a form of vibration and any vibration needs a medium thus sound needs a medium called air water etc. to propagate, sound is nothing but a disturbance caused by any source for e.g. when u hit on a table d disturbance caused there is propagated in form of waves in all directions and it can b heard by any person

see this also

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Source(s): you tube, wikipedia,self
• 9 years ago

You may refer to some books like S. Chand's Lakhmir Singh and Manjeet Kaur, or you may refer to NCERT. You can also search on Wikipedia.

• 9 years ago

i have a soln 4 u . first of all sound moves by disturbing the air molecules near it speed of it is 330 m/sec

sped varies with medium sound is faster in water.