A body is projected such that it has maximum range ‘R’ in the absence of wind. If wind imparts a horizontal acceleration ofg4then the new range is

as acceleration is in horizontal direction it will not change the time of flight and maximum height new rangewith acceleration becomes R'=ucosθT+12g4T R'= R+12g42usinθg2 R'=R+g84u2sin2θg=R+H but if θ=450 H=R4    so R'=R+R4=5R4