MHB Relationship between inner and outer radius of a two concentric circles

otlconcepts
Messages
1
Reaction score
0
If i have two circles that say 24" apart from each other. one inside the other.
and i know the radius of the inside circel, how can i calculate the outside radius
 
Mathematics news on Phys.org
Did you draw a picture?

[TIKZ]
\draw[thick,red] (0,0) circle (4);
\draw[->,thick,red] (0,0) -- (4, 0) node[below, xshift=-1cm] {$r_2$};
\draw[thick,blue] (0,0) circle (2);
\draw[->, thick, blue] (0,0) -- (2, 0) node[below, xshift=-0.75cm] {$r_1$};
[/TIKZ]

$r_2 - r_1 = 24"$ right? And you know $r_1$.
 
Last edited:
Hello, and welcome to MHB! :)

Suppose \(r\) is the radius of the inner circle and \(R\) is the radius of the inner circle, where \(k\) is the difference between the two radii:

$$R-r=k$$

mhb_0015.png
 
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. In Dirac’s Principles of Quantum Mechanics published in 1930 he introduced a “convenient notation” he referred to as a “delta function” which he treated as a continuum analog to the discrete Kronecker delta. The Kronecker delta is simply the indexed components of the identity operator in matrix algebra Source: https://www.physicsforums.com/insights/what-exactly-is-diracs-delta-function/ by...
Fermat's Last Theorem has long been one of the most famous mathematical problems, and is now one of the most famous theorems. It simply states that the equation $$ a^n+b^n=c^n $$ has no solutions with positive integers if ##n>2.## It was named after Pierre de Fermat (1607-1665). The problem itself stems from the book Arithmetica by Diophantus of Alexandria. It gained popularity because Fermat noted in his copy "Cubum autem in duos cubos, aut quadratoquadratum in duos quadratoquadratos, et...
I'm interested to know whether the equation $$1 = 2 - \frac{1}{2 - \frac{1}{2 - \cdots}}$$ is true or not. It can be shown easily that if the continued fraction converges, it cannot converge to anything else than 1. It seems that if the continued fraction converges, the convergence is very slow. The apparent slowness of the convergence makes it difficult to estimate the presence of true convergence numerically. At the moment I don't know whether this converges or not.

Similar threads

Replies
3
Views
2K
Replies
16
Views
2K
Replies
8
Views
2K
Replies
3
Views
3K
Replies
20
Views
6K
Replies
2
Views
2K
Replies
4
Views
1K
Back
Top