To solve this problem, we need to determine the maximum range of a projectile (missile) when fired with a given initial velocity. The formula for the range (R) of a projectile fired at an angle (\theta) with an initial velocity (u) is given by:
R = \dfrac{u^2 \sin(2\theta)}{g}
For maximum range, the angle of projection should be 45^\circ, meaning 2\theta = 90^\circ, hence \sin(90^\circ) = 1.
Given:
Substituting the values in the formula:
R = \dfrac{(20)^2 \times 1}{10}
Calculating further:
R = \dfrac{400}{10} = 40 \, m
Therefore, the range of the missile is 40 m, making the correct answer: 40 m.