## Question

A missile is fired for maximum range at your town from a place in the enemy country 100 km away from your town. If the missile is first detected at its half – way point, how much warning time will you have? Take *g* = 10 ms^{-2}.

### Solution

Given R_{max} = 100 km = 10^{5} m. Since the missile is fired for maximum range the angle of projection the initial velocity of the missile is since the missile is first detected at its half – way point, the warning time is half the total time of flight. Therefore,

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