Find the angle subtended at the centre of a circle of a circle of radius a by an arc of length cm. The image shows the mathematical expression 'a pi divided by 4'.

Q5 of 68 Page 15

Find the angle subtended at the centre of a circle of a circle of radius ‘a’ by an arc of lengthcm.

Radius of circle = a

Length of arc =

So,

Angle subtended at the center = 45°

An arc of length 20π cm subtends an angle of 144° at the centre of a circle. Find the radius of the circle.

An arc of length 15cm subtends an angle of 45° at the centre of a circle. Find in terms of, the radius of the circle.

A sector of a circle of radius 4cm contains an angle of 30°. Find the area of the sector.

The area of a sector of a circle of radius 2 cm iscm². Find the angle contained by the sector.