# Center of curvature

1. Apr 29, 2015

### gracy

As per ww.physicsclassroom.com/class/refln/Lesson-3/The-Anatomy-of-a-Curved-Mirror

The point in the center of the sphere from which the mirror was sliced is known as the center of curvature,I am not able to understand this.Please help.

2. Apr 29, 2015

### ZapperZ

Staff Emeritus
You have the propensity to not describe exactly what you are having a problem with. Often times, your question is very terse and short without giving much explanation on what you had attempted to do to understand it. Did you try to Google it and look it up? If you did, what did you find and what was still giving you problems? If you did not, why not?

Does this picture explain what a "center of curvature" means?

Zz.

3. Apr 29, 2015

### A.T.

4. Apr 29, 2015

### gracy

You mean we should complete the curved surface by making a circle and then center of this circle will be called "center of curvature" .Right?

5. Apr 29, 2015

### ZapperZ

Staff Emeritus
That is not necessary! Just looking at an arc of the circle is sufficient. I can take the pencil and draw just a segment of the circle. That section alone tells me where the center of curvature is.

Zz.

6. Apr 29, 2015

### gracy

Propensity can be changed,right?I will try to work on it if this is the case.
Sorry.
Yes,but didn't find any explanation useful.
ww.physicsclassroom.com/class/refln/Lesson-3/The-Anatomy-of-a-Curved-Mirror
http://en.wikipedia.org/wiki/Center_of_curvature
http://www.merriam-webster.com/dictionary/center of curvature
http://www.thefreedictionary.com/centre+of+curvature
All the definitions were hard to follow.Don't know from where @ A.T and @zapper Z got such nice and easy explanation.But yes I know I should not make excuses.I should admit that I showed less effort otherwise I too should have got these nice explanations .Because where there is a will ,there is a way!

7. Apr 29, 2015

### gracy

I was answering A.T. post.Is it still not correct?

8. Apr 29, 2015

### rumborak

To expand on this, the reason is that the circle looks the same everywhere because it is so symmetrical. If you have one tiny segment of a circle, you know what the rest will look like. And thus you know the center of that circle, the center of curvature.

9. Apr 29, 2015

### rcgldr

One way to determine the center of curvature would be a line perpendicular to the curved path, with length equal to the radius of curvature. Wiki article (includes link to radius of curvature):

http://en.wikipedia.org/wiki/Center_of_curvature

10. Apr 30, 2015

### CWatters

Centre Finder...