Ex 3.1, 5

Transcript

Ex3.1, 5 In a circle of diameter 40 cm, the length of a chord is 20 cm. Find the length of minor arc of the chord. Given Diameter = 40 cm So, Radius = r = 20 cm In figure, AB =r= 20 cm AC =r= 20 cm BC =Length of chord = 20 cm So,AB = AC = BC = 20 cm Hence Δ ABC is equilateral Hence ∠ BAC is 60° 𝜃 = 60° Hence θ = 60o = 60o × 𝜋/(180°) = 𝜋/3 Now Putting values in formula 𝑙 = r θ = 20 × (𝜋 )/3 = (20𝜋 )/3 Hence, length of minor arc of chord is (20𝜋 )/3