Normal Circle The normal to a circle is perpendicular to the tangent at the point of contact. The gradient of the gradient of the line joining the centre to the point of contact.

The image defines and illustrates the concept of a normal to a circle. A normal to a circle at a specific point is a line that is perpendicular to the tangent line at that same point. This normal line always passes through the center of the circle. In the diagram, the line labeled "Normal" passes through the center A and is perpendicular to the "tangent" line at point B. That's 2 down. 3 left today — send the next one.