What will be thrice of semi vertical angle of the cone whose curved surface area is 2 times the base area.

90º

CSA = πrl

A = πr²

r = radius of the base

l = slant height

CSA = curved surface area

A = Base area

⇒ πrl = 2πr² (given)

∴ \(\frac{r}{l}\) = \(\frac{1}{2}\)

Semiverticle angle i.e ∠CAD

Let ∠CAD = θ

sin θ = \(\frac{1}{2}\)

θ = 30°

Thrice of semiverticle angle = 3 × 30° = 90°