To verify experimentally that the tangent at any point to a circle is perpendicular to the radius through that point.
A line that touches the circle at a single point is known as tangent to a circle.
Fig. (A) Tangent to the circle
The distance from the centre of a circle to the outside edge.
A straight line that intersects a circle in two points is called a secant line.
Fig. (B) Secant of the circle
Perpendicular lines are lines that intersect at a right (90°) angle.
Shortest distance between a point and line is perpendicular distance.
