Say the perimeter of a unit cube is 12, because that's the sum of all its edges, hence it's the cube's perimeter.

What would it be for a sphere of any proportion?

Say the perimeter of a unit cube is 12, because that's the sum of all its edges, hence it's the cube's perimeter.

What would it be for a sphere of any proportion?

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TopNewestWe don't call the sum of the edge lengths of a polyhedron its "perimeter." A perimeter is the boundary of a two-dimensional figure.

Because a sphere has no edges, it has no such sum as you have defined with the cube. Your question is analogous to asking for the number of vertices of a circle. There is none. – Hero P. · 4 years, 3 months ago

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I interpret it as the sum of edges of a solid by your example of a cube. But a sphere has no edges, so the 'perimeter' is 0. If you are talking about adding all those tiny circumferences of the sphere up, you end up integrating them into the surface area of the sphere, \(4\pi r^2\). – Yong See Foo · 4 years, 3 months ago

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Correct.– Tim Ye · 4 years, 3 months agoLog in to reply

– Sanjay Ambadi · 4 years, 3 months ago

Well you're just too smart for a 14 year old. I think that is kinda the answer.Log in to reply

Tim Y. has already defined a "perimeter" of a 3D solid to be the sum of its edges. It is on our part, and not his, to understand what is implied. – Wee Xian Bin · 4 years, 3 months ago

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There is no perimeter in 3 dimensional.Please clarify your question – Edsel Salariosa · 4 years, 3 months ago

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We define perimeter for 2-dimensional figures only. – Vikram Waradpande · 4 years, 3 months ago

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i don't think it has a perimeter......as it is a 3D figure........ – Riya Gupta · 4 years, 3 months ago

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– Reshav Gupta · 4 years, 3 months ago

bebzz.... see figure chaiye 3D ho yah 2D ....hum haar time perimeter find kaar sakte hai because vo humesha hi line segments se banni hoti hai .... and the figures with curves ,,hum unka circumfrence find kaar sakte hai ...."CIRCUMFRENCE" ......................remember hum circle ka circumfrence find karte thei......... same way sphere ka bhi circumfrence nikkal sakta hai.Log in to reply

– Bob Yang · 4 years, 3 months ago

srry cant read hindi lol XDLog in to reply

– Riya Gupta · 4 years, 3 months ago

AND I would like to say one more thing.....next time dont...put ur silly...comments...in hindi.....Log in to reply

– Reshav Gupta · 4 years, 3 months ago

It's same as that of a CIRCLE .......... 2pi R = circumfrenceLog in to reply

– Aditya Parson · 4 years, 3 months ago

You cannot find the circumference of a sphere as such but you can find the circumference of the circles in it.Log in to reply

– Riya Gupta · 4 years, 3 months ago

decreasing...radii circles....will be there...Log in to reply

– Beakal Tiliksew · 4 years, 3 months ago

U are wrong,think of a sphere like a figure made of many circles of various sizes,the biggest being at the center,and decreasing gradually.what u said wouldn't make sense now would it?Log in to reply

– Riya Gupta · 4 years, 3 months ago

ohhh i guess you aren't familiar...with sphere and its properties....it cant be 2pi RLog in to reply

– Reshav Gupta · 4 years, 3 months ago

I DON'T THINK SO .......Log in to reply

– Riya Gupta · 4 years, 3 months ago

BUT I THINK SO.....AND BEFORE WRITING ANYTHING.....THINK OVER IT.......it will involve a typical integration with limits..... i think BK MAESTER T...is right.....Log in to reply

[ i said

fine! if is it so...then find "CIRCUMFERENCE" of...sphere since its a curve tooo....]

as u quoted "and the figures with curves ,,hum unka circumfrence find kaar sakte hai ...."CIRCUMFRENCE" same way sphere ka bhi circumfrence nikkal sakta hai. "

aur jab ho jae toh btana....me yahi milungi....except for the condition ki tum use kisise pucho ya fir koi search engine khol kar uspe se copy...paste karo.....huh....

[ i said when u'll finish that....post it here i'll be here only.....and terms and conditions for u.....DONT ASK IT FROM SOMEONE AND DONT CHEAT IT FROM SOME SEARCH ENGINE.....OK...] – Riya Gupta · 4 years, 3 months ago

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probably undefined since there are no edges on a sphere – Tan Li Xuan · 4 years, 3 months ago

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Well, going by your definition, lets say the sphere has infinite sides, then Perimeter = (infinity) x (whatever is the value of each side) p = ∞ But wait, the length of each side is zero as they are just points. ∴ p = ∞ x 0 = 1 (if you can consider that as true) Hence your answer is 1. – Sanjay Ambadi · 4 years, 3 months ago

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Perimeter doesn't apply to 3 dimensional figures. It is the boundary of a 2 dimensional figure.Since, 3 dimensional figures don't have any boundary , so, neither a sphere nor a cube has a perimeter. – Prakkash Manohar · 4 years, 3 months ago

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Guyss.... first of all , cube is also a 3D figure and In the figures like that of a circle or a sphere ,we don't take perimeter ,there it's circumfrence . And in sphere we can have the circumfrence .. agree? – Reshav Gupta · 4 years, 3 months ago

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