Question

Question 14.
In a circle of diameter 21cm,if an arc subtends an angle of 120° at the centre where =22/7, then what will be the length of arc.​

Answer 1

So the answer is 22222222

Answer 2

Answer:

GIVEN :-

π = 22/ 7

diameter of the circle = 21cm

angle subtended at the center  = 120°

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TO FIND :-

length of the arc

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SOLUTION :-

we know that,

∅ = l/ r .....(formula i)

where ∅ = angle subtended at the center

l = length of the arc

r = radius of the circle

diameter = 2 × r

r = diameter / 2

r = 21/2 cm

∅ = 120°

to use the formula i we need to convert the angle from degrees to radians :-

Radian measure = (π/ 180 ) × degree measure

= {22/ (7 × 180)} × 120

= (22 × 120) /  (7 × 180)

= 44/21 rad

∵ ∅ = l/ r

l = r × ∅

l = (21/2) × (44/21)

= 22

Hence, the length of the arc is 22 cm. (Ans