Question

A ball is projected horizontally from the ground of a building 19.6 m high if the line joining the point of projection to the point where it hits the ground makes an angle of 45° to the horizontal the initial velocity of the ball Is

Answer 1

as the angle 45° the range and height is going to be equal
vertical motion
Sy=ut+0.5at²
19.6=0 +0.5gt²


horizontal motion
Sx=ut
t=Sx/u
Sy=0.5g x (Sx)²/u²
Sy=Sx
u²=0.5g x 19.6
=0.5 x 9.8 x 19.6
=96.04
u²=(9.8)²
u=9.8m/s

Answer 2

Refer The Attachment

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