Question

A chord of a circle of diameter 30 cm is of length 15 cm. Find the length of mirror arc corresponding to this chord.

Answer 1

Here, AB=15 cm
OA=OB= radius of circle = 15 cm

Therefore, `DeltaAOB`, is an equilateral triangle.
`rArr angleAOB=60^(@)`
`=(60 x pi/180)` radian
`=22/(7 xx 3)` radian `=22/21` radian
`therefore` Length of minor arc = radius of circle `xx` angle subtended by this arc at the center
`=15 xx 22/21 cm = 110/7 cm = 15 (5/7) cm`.