Given that,
Angle = 30°
Initial velocity = 15 m/s
We need to calculate the time of flight
Using formula of time of flight
[tex]T=\dfrac{2u\sin\theta}{g}[/tex]
Where, u = initial velocity
g = acceleration due to gravity
Put the value into the formula
[tex]T=\dfrac{2\times15\sin30}{9.8}[/tex]
[tex]T=1.5\ sec[/tex]
We need to calculate the final velocity of the ball
Using equation of motion
[tex]v=u+gt[/tex]
[tex]v=15+9.8\times1.5[/tex]
[tex]v=29.7\ m/s[/tex]
Hence, The final velocity of the ball is 29.7 m/s.