Tangent to a Circle
Tangent to a Circle: Overview
This topic explains the tangent to a circle. The word ‘tangent’ was introduced by the Danish mathematician Thomas Fineke. It comes from the Latin word ‘tangere’, which means to touch. It is a line that intersects the circle at only one point.
Important Questions on Tangent to a Circle
In a park, four poles are standing at positions and around the fountain such that the cloth joining the poles and touches the fountain at and respectively as shown in figure:
Based on the above information, answer the following question:
If is the centre of the circular fountain, then

Draw a tangent at any point on the circle having radius units

The tangent to a circle is a special case of the secant when the two endpoints of corresponding chord coincide

The tangent to a circle is a special case of the secant.

Two concentric circles are of radii and . Find the length of the chord of the larger circle which touches the smaller circle in .

From a point , the length of the tangent to a circle is and the distance of from the centre is . The radius of the circle is

From a point the length of the tangent to a circle is and the distance of from the centre is . Find the radius of circle in .

The tangent to a circle is a special case of the secant, when the two end points of its corresponding chord coincide.

A circle with centre at touches the four sides of a quadrilateral internally in such a way that it divides in and . If the radius of the circle is , where , find the value of .

Two parallel lines touch the circle at points and , respectively. If area of the circle is, then is equal to

is a cyclic quadrilateral and is a tangent to the circle at . If is a diameter, and then find the measure of (write answer without degree symbol) is

is a cyclic quadrilateral and is a tangent to the circle at . If is a diameter, and , the measure of . Then find the value of

To draw a pair of tangents to a circle which are inclined to each other at an angle of , it is required to draw tangents at the end points of those two radii of the circle. If the angle between them is , then the value of is

The point at which a tangent is perpendicular to the radius is called point of _____ (centre, tangency, radius)
