Find the lengths of the arcs cut off from a circle of radius 12 cm by a chord 12 cm long. Also, find the area of the minor segment.
[Takeπ=3.14and√3=1.73]
ANSWER:
Let AB be the chord. Joining A and B to O, we get an equilateral triangle OAB.
Thus, we have:
O=∠A=∠B=∠120∘.
Length of the arc ACB:
2π×12×60360=4π=12.56cm
Length of the arc ADB:
Circumference of the circle - Length of the arc ACB=2π×12−4π=20πcm=62.80cm
Now,
Area of the minor segment:
Area of the sector - Area of the triangle=π×(12)2×60360−√34×(12)2=13.08cm2