State whether the following statement is 'True' or 'False' and provide reasons for your answer: The length of a tangent from an external point to a circle is always greater than the radius of the circle.

Vedclass pdf generator app on play store
Vedclass iOS app on app store
(B) The statement is 'False'.
Let the radius of the circle be $r$ and the length of the tangent from an external point $P$ be $L$.
In a right-angled triangle formed by the radius, the tangent, and the line segment connecting the center to the external point, the hypotenuse is the distance from the center to the external point $(d)$.
By the Pythagorean theorem, $d^2 = r^2 + L^2$.
Since $d > r$, it follows that $L = \sqrt{d^2 - r^2}$.
Depending on the distance $d$ of the external point from the center, the length of the tangent $L$ can be greater than, equal to, or less than the radius $r$.
For example, if the external point is very close to the circle, the tangent length can be smaller than the radius.

Explore More

Similar Questions

$A$ tangent to a circle is perpendicular to ..... drawn from the point of contact.

$A$ line drawn from the centre $O$ of a circle with radius $7 \, cm$ intersects the tangent at point $P$ on the circle at point $Q$,such that $PQ = 24 \, cm$. Find $OQ$.

In the figure,$O$ is the centre of a circle of radius $5 \, cm$. $T$ is a point such that $OT = 13 \, cm$ and $OT$ intersects the circle at $E$. If $AB$ is the tangent to the circle at $E$,find the length of $AB$ in $cm$.

Difficult
View Solution

$P$ is a point in the exterior of a circle having centre $O$ and radius $21$. $OP = 25$. $A$ tangent from $P$ touches the circle at $Q$. Find $PQ$.

From an external point $P$,two tangents,$PA$ and $PB$ are drawn to a circle with centre $O$. At one point $E$ on the circle,a tangent is drawn which intersects $PA$ and $PB$ at $C$ and $D$,respectively. If $PA = 10 \, cm$,find the perimeter of the triangle $PCD$ (in $cm$).

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo