Answer:
Explanation:
Ball rises and falls in equal periods. Because it goes by same speeds and same route. Therefore t_{rise} = t_{fall} =2.5 s
In free fall and vertical throw movement: x= (1/2).a.t^{2}
Here, we can find the height of the ball
x= (1/2).5.(2.5^{2}) = 15.625 m
From the attaches V-t graphics, x=V.t/2
15.624=V.(2.5)/2
V=12.5 m/s
