Answer:
11.44 m/s
Explanation:
We are given;
Initial Speed of ball;v_o = 30 m/s
Distance from person to ball;d = 70 m
Now, from projectile motion, the ball will hit the ground in time given by the formula;
t = (2v_o)/g
Wherr;
t is time taken
v_o is initial velocity
g is acceleration due to gravity
Plugging in the values with g = 9.8 m/s² as acceleration due to gravity, we have;
t = 2(30)/9.8
t = 6.12s
Now, the person will need to run 70m in 6.12s
We know that velocity/speed = distance/time
Thus;
Speed = 70/6.12
Speed = 11.44m/s
