Let slant height of the first cone = ℓ
then slant height of the second cone = 2ℓ
Radius of the first cone = r1
Radius of the second cone = r2
Then, curved surface area of first cone = π r1 ℓ
curved surface area of second cone = π r2 (2ℓ) = 2π r2 ℓ
According to given condition: