- #1

dom_quixote

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The proportions of a circle never change. But...

Question:

If a circle is always a circle, then how is it possible that the S/L and {[S/L]/R} ratios of a circle can vary as a function of the radius size?

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- Thread starter dom_quixote
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- #1

dom_quixote

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The proportions of a circle never change. But...

Question:

If a circle is always a circle, then how is it possible that the S/L and {[S/L]/R} ratios of a circle can vary as a function of the radius size?

- #2

Office_Shredder

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- #3

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There are errors in your table for the perimeter. It should read 2/5π and ~~3/5π~~ 2/3π for the first two. And S/L for R=1/2 is 1/4, not 1.

Last edited:

- #4

hutchphd

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##\frac 2 3 \pi## ?There are errors in your table for the perimeter. It should read 2/5π and 3/5π for the first two. And S/L for R=1/2 is 1/4, not 1.

- #5

A.T.

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Try it with a square if you have problems understanding it for a circle. It's more a geometry question rather than physics.If a circle is always a circle, then how is it possible that the S/L and {[S/L]/R} ratios of a circle can vary as a function of the radius size?

Related topic:

https://en.wikipedia.org/wiki/Square–cube_law

- #6

The Fez

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- #7

dom_quixote

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In fact, I made a mistake .

The corrected table is below:

Note in the TABLE I a singularity, when R=2/1:

S = L ?

Certainly not!

S expresses area;

L expresses length.

P.S.:

If there is another error in the table, I apologize for my numerical dyslexia !

The corrected table is below:

Note in the TABLE I a singularity, when R=2/1:

S = L ?

Certainly not!

S expresses area;

L expresses length.

P.S.:

If there is another error in the table, I apologize for my numerical dyslexia !

Last edited:

- #8

DaveE

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Since ##S=\pi R^2## and ##L=2 \pi R## then ##\frac{S}{L} = \frac{\pi R^2}{2 \pi R} = \frac{R}{2}## and ##\frac{(\frac{S}{L})}{R} = \frac{1}{2}##.

That is all there is to this, now you can correct your tables.

- #9

A.T.

Science Advisor

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They can have have the same numerical value (which is what your table shows), but different units (which your table doesn't show).S = L ?

Certainly not!

S expresses area;

L expresses length.

See post #6 and #8.If there is another error in the table, I apologize for my numerical dyslexia !

- #10

Mark44

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Why don't you use letters that more closely align with what they represent?Note in the TABLE I a singularity, when R=2/1:

S = L ?

Certainly not!

S expresses area;

L expresses length.

R is fine for radius, but why are you using S for area and L for length? Better would be A for area and P or C for either perimeter or circumference.

Or even some simple arithmetic.How about applying some simple algebra before you make the tables?

You have errors in the first two rows of table 1.

##2\pi \frac 1 5 \ne \frac{5\pi} 2##

##2\pi \frac 1 3 \ne \frac{3\pi} 2##

Last edited:

- #11

Mark44

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The initial questions have been asked and answered, so I'm closing this thread.

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