Question

A missile is fired for maximum range with an initial velocity of $20\text{m/s}$. If $g=10{\text{m/s}}^2$, the range of the missile is :

• A. $50\text{m}$
• B. $20\text{m}$
• C. $60\text{m}$
• D. $40\text{m}$

Answer 1

The correct option is D $40\text{m}$

Given:
initial velocity $u=20\text{m/s}$
$g=10{\text{m/s}}^2$
We know that, for maximum range the angle of projection $\theta ={45}^{\circ }$
so,
$R_{max}=\frac{u^2\sin 2\theta }{g}=\frac{{20}^2\sin {90}^{\circ }}{10}=\frac{20\times 20}{10}=40\text{m}$.
Hence, option $\left(A\right)$ is correct.