Question

An artillary piece which consistently shoots its shells with the same muzzle speed has a maximum range R. To hit a target which is R/2 from the gun and on the same level, the elevation angle of the gun should be 

(a) 15° 

(b) 45° 

(c) 30° 

(d) 60

Answer 1

Correct option  (a) 15°

Explanation:

Range of a projectile is maximum when it is projected at an angle of 45° and is given by

where u is the velocity of projection

Now, to hit a target at a distance (R/2) from the gun, we must have