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Author Topic: Geometry answer I can't find  (Read 3868 times)

Norseman

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Geometry answer I can't find
« on: December 03, 2011, 01:41:44 AM »

Hi Folks

This is a simple enough question that has bothered me (for no reason at all) for years -

What is the name of the point at which two spheres meet/kiss?

............ yes I can get a bit obsessive about small things ........... like

words ending 'shion' - cushion, fashion, because I was told years ago that there was a third? Beats me.

Dave
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w3bby

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Re: Geometry answer I can't find
« Reply #1 on: December 03, 2011, 03:17:03 AM »

words ending 'shion' - cushion, fashion, because I was told years ago that there was a third? Beats me.

http://uk.answers.yahoo.com/question/index?qid=20060704074007AAEKPS5
and that mystery is solved .

The other??????

RaaArtyGunner

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Re: Geometry answer I can't find
« Reply #2 on: December 03, 2011, 04:21:30 AM »

Hi Folks

This is a simple enough question that has bothered me (for no reason at all) for years -

What is the name of the point at which two spheres meet/kiss?


Dave

A line that passes and touches a point on a sphere/circle is a tangential line, it is at right angles (90 Degrees) to the radius, so maybe that point where circles touch is the Tangent point as you would be able to draw a tangential line, which would be at right angles to both circles, between them at the tangent point.

Anyone else ????
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derekwarner

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Re: Geometry answer I can't find
« Reply #3 on: December 03, 2011, 04:27:54 AM »

it is OK Dave  {-) ...are you talking .....about the point where surface tension or surface pressure ....acting on the two spheres forces 'them' together to make a double volume sphere?   :o

It certainly happens in nature  :-)) .....it also happen in PHOTOSHOP advertisements for Mortein fly spray  :kiss: ..................Derek

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Norseman

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Re: Geometry answer I can't find
« Reply #4 on: December 03, 2011, 02:54:29 PM »

Thanks for Fushion and Parishion.

Yes I had thought of a tangential point but that general term wouldn't be specific only to where spheres touch each other.

Derek I am thinking about spheres as if they are Plato's shapes - existing only as an idea and therefore capable of being perfect - no line ever actually formed or drawn is perfect - even a single atom would have a shape. So in that sense the distance between the spheres would be the thickness of the tangential plane (which I think is 0) and the area of contact (and this really freaks me out) must also be zero ......... so although there is no distance between them, how are they touching at all? I was just contemplating what this point would be called - find it hard to believe some mathematician has named it (after himself probably).

At this juncture I want to say I know nothing at all about maths  %%............. which might be obvious to those Mayhemers who do O0

Regards Dave
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Netleyned

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Re: Geometry answer I can't find
« Reply #5 on: December 03, 2011, 04:16:03 PM »

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Norseman

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Re: Geometry answer I can't find
« Reply #6 on: December 03, 2011, 05:09:14 PM »

Well Ned I looked at the link - but I didn't understand any of the math there, though I did see someone also state the distance = 0. No mention of the area = 0 or of a name. Thanks for looking anyway.

Daft thing is the question has no importance at all but it is just bugging me. %%

Dave

ps In a minute I am going to post up a nice normal question about what to make with a red ebay hull
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Netleyned

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Re: Geometry answer I can't find
« Reply #7 on: December 03, 2011, 05:13:36 PM »

Red Ebay?
Russian is it?

Ned
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Norseman

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Re: Geometry answer I can't find
« Reply #8 on: December 03, 2011, 05:31:37 PM »

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Umi_Ryuzuki

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Re: Geometry answer I can't find
« Reply #9 on: December 03, 2011, 06:17:18 PM »

Hi Folks

This is a simple enough question that has bothered me (for no reason at all) for years -

What is the name of the point at which two spheres meet/kiss?

............ yes I can get a bit obsessive about small things .........

Dave

I would call that point an " illu-shion " because a point has 
zero length, zero area, and zero volume. And for two points to meet, they must occupy the same space.

 :o

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tt1

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Re: Geometry answer I can't find
« Reply #10 on: December 03, 2011, 06:41:57 PM »

Nice one Umi !

With you on this one Ned, why does everything have to be in a foreign language?  {-) {-) {-)
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Norseman

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Re: Geometry answer I can't find
« Reply #11 on: December 03, 2011, 07:38:27 PM »

Hi Umi

loved the shion use there - very witty :}

but two points that meet don't occupy the same space, they just occupy adjacent spaces like cars parked bumper to bumper. (Lol if they occupy the same space they have crashed) {-)

Dave (and I'm still working towards that Kalakala model Umi)
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RaaArtyGunner

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Re: Geometry answer I can't find
« Reply #12 on: December 03, 2011, 09:00:27 PM »

Nice one Umi !

With you on this one Ned, why does everything have to be in a foreign language{-) {-) {-)

Because English is the universal language  :-)) :-)) %) %) %)
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ACTion

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Re: Geometry answer I can't find
« Reply #13 on: December 03, 2011, 11:06:33 PM »

Why not call it "Jim"?
DM
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Norseman

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Re: Geometry answer I can't find
« Reply #14 on: December 04, 2011, 12:52:45 AM »

I'd prefer The 'Dave' point for 'Daft And Very Elusive'

Dave
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Dreadstar

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Re: Geometry answer I can't find
« Reply #15 on: December 04, 2011, 06:22:40 AM »

Are you thinking about the point of intersection Norseman?
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Norseman

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Re: Geometry answer I can't find
« Reply #16 on: December 04, 2011, 02:50:24 PM »

Hi Dreadstar

this is hurting my brain because I don't have  the language of maths - I am more a artistic leaning guy than science but I'll try

if it were two lines lying in the same plane, then no because obviously they cross. Now I have found out that you can have a point of intersection between two curves, but again I am thinking that these curves must actually cross each other  to 'intersect'. Lets think of two dimensional arcs - you could arange them so as to have a single point of intersection or so as to have two points of intersection.You could also arrange them )( touching but not breaking each other.

Thinking in three dimensions - for spheres - and if intersecting requires cutting the plane - then there is not a point/s of intersection but there is instead a continuous plane of intersection. What I am seeking (and as above I emphasise this is for ideal shapes) is a name (applicable specifically to spheres) where they meet but do not intrude upon one another's planes.

This specific name of this point might not exist, but I find that hard  to believe because one a concept is named (so can be learnt) it can be applied more readily to problems. I did look at some explanation of packing tennis balls thinking I might come across what I was looking for.

It's just something I was thinking about and that's surprising in itself  %%
Maybe we have a Mathemetician out there in Mayhemland who is laughing his socks off - I really hope so {-) %%

Dave
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Jonty

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Re: Geometry answer I can't find
« Reply #17 on: December 04, 2011, 03:53:22 PM »

~C = position of the contact point between two spheres (a three dimensional vector referring to global coordinate system).

  That's meant to be a C with a right-pointing arrow over it. Like you, I had rather hoped to find a nice Greek word...
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dodgy geezer

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Re: Geometry answer I can't find
« Reply #18 on: December 04, 2011, 05:26:38 PM »


... So in that sense the distance between the spheres would be the thickness of the tangential plane (which I think is 0) and the area of contact (and this really freaks me out) must also be zero ......... so although there is no distance between them, how are they touching at all? ...


They touch at the point. In geometry, points are zero-dimensional. So quantities like distance are not an issue...
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Norseman

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Re: Geometry answer I can't find
« Reply #19 on: December 07, 2011, 10:07:28 PM »

Hi lads

thanks for the replies - all interesting stuff

Dave
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RaaArtyGunner

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Re: Geometry answer I can't find
« Reply #20 on: December 07, 2011, 10:29:42 PM »

So are you any the wiser  O0 O0 O0 ;) ;) ;)
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Norseman

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Re: Geometry answer I can't find
« Reply #21 on: December 07, 2011, 10:35:19 PM »

 %% {-)  I don't know  {-) %%

You can't always get what you want, but if you try sometimes, you get what you need ...............

now just who said that?

Dave
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Abuelo3

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Re: Geometry answer I can't find
« Reply #22 on: December 07, 2011, 11:04:08 PM »

the point where two round figures touch maybe the umbilical zone????? ;D :embarrassed:
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Norseman

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Re: Geometry answer I can't find
« Reply #23 on: December 07, 2011, 11:13:42 PM »

Both I and the wife are two round figures but ..................... Nah {-) {-) {-)
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