Question

In a circle of radius 35 cm, an arc subtends an angle of 72° at the centre. Find the length of the arc and area of the sector.

Answer 1

Given, 

Radius of circle = 35 cm 

Angle subtend by arc = 72° 

Length of arc = r×q 

Since, 

180° = π radius 

1° = \(\frac{π}{180°}\)

72° = \(\frac{π\times72°}{180°}\) = \(\frac{2π}5\) radius

Length of the arc = 35 x 2 x \(\frac{22}{7}\times\frac{1}{5}\) = 44 cm

Area of sector = \(\frac{θ}{360°}\timesπr^2\)

= \(\frac{72°}{360°}\times\frac{22}{7}\times35\times35\)

= 770 cm²