A particle is projected with a velocity v such that its range on the horizontal plane is twice the greatest height attained by it. The range of the projectile is (where g is acceleration due to gravity)
R = 2H given
We know R = 4H cot θ ⇒ cot θ = 12
From triangle we can say that sin θ = 2√5, cos θ = 1√5
∴ Range of projectile R = 2v2sinθcosθg
= 2v2g × 2√5 × 1√5 = 4v25g