# Thread: Vertical distance between 2 points on a circle

1. ## Vertical distance between 2 points on a circle

Hi Guys,

I've got a (to me anyway) challenging problem, which I hope you could give me a hand with.

I've calculated the radius of curvature of a circle (200m) and thus the curvature (1 / 200). I need to find the vertical distance (y in diagram) and the horizontal distance (x in diagram) between 2 points A and B. I also know that the arc length of AB is 2x10-3.

Any ideas?

2. ## Curvature

Originally Posted by geomnew
Hi Guys,

I've got a (to me anyway) challenging problem, which I hope you could give me a hand with.

I've calculated the radius of curvature of a circle (200m) and thus the curvature (1 / 200). I need to find the vertical distance (y in diagram) and the horizontal distance (x in diagram) between 2 points A and B. I also know that the arc length of AB is 2x10-3.

Any ideas?
I'm afraid this is not possible unless you know the direction of the curve in the region of these points -its gradient, if you will. Just knowing the curvature at this point is not sufficient - for this does not fix the directions of x and y.

Grandad