Birth Of The Universe In 5 Seconds

[manker]

You can't have sound in a vacuum.

that's a very common misconception.

it is true if the vacuum is perfect - i.e. if there are no molecules of air at all present in some enclosed space - but perfect vacuums are not common place.

now if, for example, you suck the tip of your finger to create a vacuum inside your mouth (so your cheeks are concave) then you haven't expelled all of the air so sound can still travel in that small space. sound just needs some air molecules to compress together in order to be able to travel.

yes. I'm bored, waiting for the football to start. ]

I said vacuum, not partial vacuum.

I did not qualify the word in any way, so what you posted was totally irrelevant.

You described my argument as a common misconception, then the next thing you said was that it was true. Whether a perfect vacuum is commonplace is neither here nor there.

You can't have sound in a vacuum.

eh? you said "You can't have sound in a vacuum."

but

a vacuum is a given space filled with gas at pressures below atmospheric pressure. this is not limited to a given space with no gas present at all below atmospheric pressure but it does encompass it.

therefore for reasons I've given you can have sound in a vacuum

further:

the notion that there cannot be sound in a vacuum is a common misconception

as you have just ably demonstrated.

dress it up how you want. you're wrong.

[J'Pol]

A vacuum is a space empty of matter.

You may chose to use an (acceptable) alternative meaning. However the true scientific definition of a vacuum is a space devoid of matter.

You can't get sound in a vacuum.

[manker]

Originally posted by J'Pol@25 June 2004 - 09:16
A vacuum is a space empty of matter.

You may chose to use an (acceptable) alternative meaning. However the true scientific definition of a vacuum is a space devoid of matter.

You can't get sound in a vacuum.

Oh, I see. you're confused as to what a vacuum is. I'm afraid your definition is incomplete.

Those chaps at N.A.S.A. may blow a disproportionately large amount of public money on what many consider to be frivolities but when it comes to vacuum spec, they know their onions.

Note the different levels of stregnth. vacuums are measured in torrs, the lower the torr the less matter inside the vacuum in proportion to the volume of the enclosed space. thus vacuums are generally not deviod of matter and precisely because they are not deviod of matter sound will travel through them.

This isn't a fuzzy theological debate. it's science where you're either correct or incorrect. that is why I say you can dress it up how you want but clearly you are wrong. don't feel bad because as I said before it is a common misconception

Sound can travel through a vacuum.

[J'Pol]

I don't feel bad at all, as I am right.

Merriam Webster gives us

1 : emptiness of space
2 a : a space absolutely devoid of matter b : a space partially exhausted (as to the highest degree possible) by artificial means (as an air pump) c : a degree of rarefaction below atmospheric pressure

Dictionary.com gives us

Absence of matter.
A space empty of matter.
A space relatively empty of matter.
A space in which the pressure is significantly lower than atmospheric pressure.
A state of emptiness; a void.

In each case look at the first meaning. Generally the first meaning is the commonly accepted one and those following are alternates.

Your argument is based on the contention that a vacuum can contain matter. When I studied physics that was known as a partial vacuum, only space totally devoid of matter was considered to be a vacuum.

The problem here is in our definitions. If we take a vacuum by my definition (and the first one in both dictionary's I have quoted) then you can't have sound in a vacuum.

If you use your definition, i.e. a space in which the pressure is significantly lower than atmospheric pressure, then yes you can have sound.

We are both right / wrong depending on the definition used.

[manker]

We can't both be right, sound can either travel in a vacuum or it cannot.

Merriam Webster says a vacuum can be partially deviod of matter as does dictionary dot com

Your reasoning is flawed as your 'definition' of a vacuum isn't a definition at all, it's an example.

my definition encompasses all instances of vacuums.

In the first message you stated that "sound cannot travel in a vacuum" that is clearly untrue because Merriam Webster, dictionary dot com and N.A.S.A have all catagorically stated that just because a vacuum has matter inside it does not preclude it from being a vacuum.

Therefore sound can travel in a vacuum.

edit: I'm off to Newquay for a stag weekend in 20 minutes. maybe we can pick this up on Monday or something because something tells me you wont just say "good point manker, I stand corrected"

[J'Pol]

Unfortunately I won't be here for a week or so, as of tomorrow.

However good point manker, well presented, incorrect as it may be.

Enjoy your weekend btw. I hope you have a great time.

[manker]

your wit surpasses mine but your logic does not in this matter! but have a good week yourself, whatever you're getting up to.

btw I've just re-read my last post, as I hurried it rather, it seems that this is the killer point in my favour:

Your reasoning is flawed as your 'definition' of a vacuum isn't a definition at all, it's an example.

my definition encompasses all instances of vacuums.

ok I'm outta the door

[J'Pol]

Originally posted by manker@25 June 2004 - 14:01
your wit surpasses mine but your logic does not in this matter! but have a good week yourself, whatever you're getting up to.

btw I've just re-read my last post, as I hurried it rather, it seems that this is the killer point in my favour:

Your reasoning is flawed as your 'definition' of a vacuum isn't a definition at all, it's an example.

my definition encompasses all instances of vacuums.

ok I'm outta the door

TTFN

Oh and, as and when it is decided that either you, NASA or both of you are the arbiter(s) of use of the English Language then I may perhaps be forced to take heed.

However till then I will be forced to work the old fashioned way and read what the dictionary has to say.

Dictionaries provide definitions, that is their job ever since Dr Johnston had his spiffing idea . So when I quote dictionaries I provide a definition, not an example.


PS, let's look at the etymology of the word

vacuum - 1550, from L. vacuum "an empty space, void," noun use of neuter of vacuus "empty," related to vacare "be empty."

NB Not emptyish


There can't be sound in a space which contains no matter (they should invent a word for that).

[Busyman]

Jumping in late....

The whole argument regarding the sound of the Big Bang is utter bullshit.

How can they reconstruct the sound of the Big Bang if there even was a Big Bang?

[J'Pol]

Originally posted by Busyman@25 June 2004 - 14:35
Jumping in late....

The whole argument regarding the sound of the Big Bang is utter bullshit.

How can they reconstruct the sound of the Big Bang if there even was a Big Bang?

You can't have sound in a vacuum.