Physics - sounds waves
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does pitch increase when you tighten the membrane of a drum? i have no idea what exactly is that. i mean the "membrane" of the drum.
and can someone show me a diagram depicting a wavelength between the rarefactions and compressions? is the wavelength the length between a series of rarefactions and compressions?
lastly, what does the question mean when it says to indicate the centres of compressions and rarefactions?
much thanks!
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yes, the pitch go higher for every bit more tightened. lower if released, but until a certain point, the drum goes "blok blok blok" and has no more useful response.
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does pitch increase when you tighten the membrane of a drum? i have no idea what exactly is that. i mean the "membrane" of the drum.
Yes. Membrane is sort of the 'skin' of the drum, the place where you hit the drum with your drumsticks. The tighter it is, the faster it will vibrate, thus higher frequency and thus higher pitch.
and can someone show me a diagram depicting a wavelength between the rarefactions and compressions? is the wavelength the length between a series of rarefactions and compressions?
Wah lau... you really jialat leh... this one should be very basic...
wavelength is distance between the centre of consecutive rarefactions or consecutive compressions.
lastly, what does the question mean when it says to indicate the centres of compressions and rarefactions?
Literally the centre....
Regards,
Eagle (ExamWorld) -
Let's say we have a sound wave that goes like this:
l l l l l l lll l l l l l l l l l l l l l lll l l l l l l (not a very good diagram though)
Anyway, the wavelength will be the length between 2 consecutive compressions/rarefactions, for this case, let's use the compressions since it is easier to notice the compressions for this diagram. The wave length is indicated between the two 'red lines'.At the same time, the 'red lines' are actually the centres of compressions. As for the centre of the rarefaction (in the diagram you can only determine one centre of rarefaction), it is indicated by the blue line. It is like determining by 'length' where is the 'middle' of a rarefaction and a 'middle' of a compression.
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best diagram. I would draw it this way too.
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that's a good idea to draw!
I always draw it this way...
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ok! thanks all!