Answer:
45°
Explanation:
Range is the horizontal distance travelled by an object undergoing projectile motion.
Range is given by the formula:
[tex]R=\frac{u^2sin(2\theta)}{g}[/tex]
where u = velocity, g = acceleration due to gravity and θ = angle above the horizontal.
For angle of 15°:
[tex]R=\frac{u^2sin(2*15)}{g}=\frac{0.5u^2}{g}[/tex]
We get a maximum range when sin(2θ) = 1
sin(2θ) = 1
2θ = sin⁻¹(1)
2θ = 90⁰
θ = 90°/2
θ = 45⁰
For angle of 45°:
[tex]R=\frac{u^2sin(2*45)}{g}=\frac{u^2}{g}[/tex]