A circle of radius, R is made to rotate about a known offset(adsbygoogle = window.adsbygoogle || []).push({});

distance,e from its center. Now the polar equation for the profile

will be e-e*cos(theta)+constant, with theta the angle from reference.

As I understand, the radius of curvature of this curve should be a

constant R. Surprisingly, when I use the polar rad. of curv. eqn. I

get a varying radius of curvature instead of constant, R.

For example, if R=2 and e=1. This will give r(@) eqn as 1+(1-1*cos

(@)) I get rad. of curvature varying (cyclic)from approx. 1.8 to 2

instead of constant 2.

Why the rad. of curvature should vary for a circle, eventhough it is

rotated about offset center?

Is it true for offset circle that at any time the osculating circle

at any point should be the circle of radius,R ?

If it is true, why the polar curvature formula is not working here?

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# Radius of curvature of an offset circle

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