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[Norseman]

Hi


Just a random couch thought, but does anyone know the name of the point at which two spheres touch? I don't know the answer but I'm sure we will have a 'magicmagician' somewhere on Mayhem - probably in Oz 


To make the question explicit let's say the spheres are identical, perfect, and are also imaginary so there is no issue of not being spherical at a molecular level.


Dave

[Netleyned]

Simply the 'point' I would have thought.


Ned

[Norseman]

You could well be right Ned but scientists engineers and magicmajicians seem to have a name for everything and I wondered?

[kinmel]

In an arranged group of spheres each contact is at a "lattice point", no idea about just 2 spheres.

Is it different if they touch internally, rather than externally ?

[Norseman]

I was just thinking externally but there may be a difference. I'm having knee pains today and resting them has me bored silly, hence the idle question.

[essex2visuvesi]

I thought it was an intersection

[kinmel]

It could well be.

[Bob K]

Also having little to do I have been googling at length.  It appears it is just a "point" where they meet.

[Netleyned]

There seems to be a great deal of complicated maths to calculate the size
of the point, but no terminology as to a name other than point.

Ned

[ballastanksian]

Why can't they meet at a cafe or go for a pint?

Seriously though: Accordong to Wiki, the intersection of two disks is called the 'Lens'. Given that the exterior of a sphere is curved, and lenses are also basically a curved face, it is logical to call the pit that two spheres meet a 'Lens'.

[Norseman]

Ah from your diagram it becomes obvious that it is the kissing point 
I've finally found a use for that emoticon.

[Bob K]

Seriously though: Accordong to Wiki, the intersection of two disks is called the 'Lens'. Given that the exterior of a sphere is curved, and lenses are also basically a curved face, it is logical to call the pit that two spheres meet a 'Lens'.

That only applies if they intersect, otherwise a theoretical point contact is still a 'point'.