Question : If two tangents inclined at an angle of 120° are drawn to a circle of radius 6 cm, then what is the length (in cm) of each tangent?
Option 1: $3 \sqrt{3}$
Option 2: $2 \sqrt{3}$
Option 3: $4 \sqrt{3}$
Option 4: $\sqrt{3}$
Recommended: How to crack SSC CHSL | SSC CHSL exam guide
Don't Miss: Month-wise Current Affairs | Upcoming government exams
Correct Answer: $2 \sqrt{3}$
Solution :
Let O be the centre of the given circle.
Let AB and AC be the two tangents to the given circle drawn from point A.
$\therefore$ $\angle BAC = 120°$
Now OB and OC represent the radii of the circle
$\therefore OB \perp AB$ and $OC \perp AC$
Since the radius of a circle is perpendicular to the tangent,
the line joining the intersection of tangents to a circle's centre will bisect the tangent's angle.
$\therefore \angle BAO = 60°$
In $\triangle ABO,$
$\frac{OB}{AB} = \tan\angle BAO$
$⇒\frac{OB}{AB} = \tan 60° = \sqrt3$
$\therefore AB = \frac{OA}{\sqrt3} = \frac{6}{\sqrt3} = 2\sqrt3$
Hence, the correct answer is $2\sqrt3$.
Related Questions
Know More about
Staff Selection Commission Combined High ...
Answer Key | Eligibility | Application | Admit Card | Preparation Tips | Result | Cutoff
Get Updates BrochureYour Staff Selection Commission Combined Higher Secondary Level Exam brochure has been successfully mailed to your registered email id “”.




