A chord of a circle has a length of 12 cm. The angle subtended by the chord at a point on the circumference is 30. What is the distance from the center of the circle to the chord?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. cm.
Angle at circumference = 30°
So angle at center = 2 × 30° = 60°
Chord = 2r sin()
⇒ 12 = 2r sin30°
⇒ 12 = 2r ×
⇒ 12 = r
So, radius = 12 cm
Distance from center to chord(d) = r cos(θ\over2)
⇒ 12 cos30° = 12 × = 6√3 cm