Question

In a circle of radius 21cm, an arc subtends an angle of 60° at the centre. Find
length of the arc and area of the sector formed by the arc.​

Answer 1

Answer:

In the mentioned figure,

O is the centre of circle,

AB is a chord

AXB is a major arc,

OA=OB= radius =21 cm

Arc AXB subtends an angle 60   at O.  

i) Length of an arc AXB =  360 /60 ×2π×r

                                         = 1/6×2×  22/7×21

                                          = 22cm

​ii) Area of sector AOB =  60 /360×π×r^2    

                                      = 1/6× 22/7×[21]^2

                                      =  231cm

hope it helps u.

                                         

                                         

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