Answer:
a) Vi = 137.2 m/s
b) h = 960.4 m
Explanation:
a)
In order to find the initial speed we will use first equation of motion:
Vf = Vi + gt
where,
Vf = Final velocity = 0 m/s (since ball stops at highest point)
Vi = Initial Velocity = ?
g = - 9.8 m/s² (negative sign for upward moyion)
t = time interval = 14 s
Therefore,
0 m/s = Vi + (-9.8 m/s²)(14 s)
Vi = 137.2 m/s
b)
Now, we use second equation of motion to find height (h):
h = Vi t + (1/2)gt²
h = (137.2 m/s)(14 s) + (1/2)(-9.8 m/s²)(14 s)²
h = 1920.8 m - 960.4 m
h = 960.4 m
