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Question:

Two particles are projected from the same point with the same speed such that they have the same range R, but different maximum heights, h1 and h2. Which of the following is correct?

R2=16h1h2

R2=h1h2

R2=2h2h2

R2=4h1h2

Solution:

Correct option is B. R²=16h₁h₂
For same range angle of projection will be θ and 90-θ
R = u²/g * 2sinθcosθ
h₁ = u²sin²θ/g
h₂ = u²sin²(90-θ)/g = u²cos²θ/g
R² = (u⁴/g²) * 4sin²θcos²θ
h₁h₂ = (u⁴/g²)(sin²θcos²θ)
R² = 4(u⁴/g²)(sin²θcos²θ) = 16h₁h₂