a****a
发帖数: 21 | 1 I am not smart enough, so honestly ask help for a very simple question or any
idea to solve this problem:
If a circular plate has diameter x, and a very small ball has diameter y, what
is the maxmum number of small balls can be placed on the circular plate? | s******e
发帖数: 92 | 2 Is it simple?....
co-ask...
any
what
【在 a****a 的大作中提到】
: I am not smart enough, so honestly ask help for a very simple question or any
: idea to solve this problem:
: If a circular plate has diameter x, and a very small ball has diameter y, what
: is the maxmum number of small balls can be placed on the circular plate?
| M*********e
发帖数: 1988 | 3 This is the packing lemma. You can use area to get a loose bound.
Each ball's center must be inside the plate. And two balls are disjoint.
So say there are N balls. The total area of the balls is N* pi * (y/2)^2.
This is no more than \pi *(x/2+y/2)^2. So N \leq (1+x/y)^2.
The optimum value is still open.
any
what
【在 a****a 的大作中提到】
: I am not smart enough, so honestly ask help for a very simple question or any
: idea to solve this problem:
: If a circular plate has diameter x, and a very small ball has diameter y, what
: is the maxmum number of small balls can be placed on the circular plate?
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