Answer:
25 m
9.9 m/s
22 m/s
Explanation:
m = Mass of ball
v = Velocity
g = Acceleration due to gravity = 9.81 m/s²
Applying conservation of energy
[tex]mgh=\dfrac{1}{2}mv^2\\\Rightarrow h=\dfrac{v^2}{g}\\\Rightarrow h=\dfrac{10^2}{2\times 9.81}\\\Rightarrow h=5.09683\ m[/tex]
The height above the ground is 5.09683+20 = 25.09683 m = 25 m
[tex]mgh=\dfrac{1}{2}mv^2\\\Rightarrow v=\sqrt{2gh}\\\Rightarrow v=\sqrt{2\times 9.81\times 5}\\\Rightarrow v=9.9\ m/s[/tex]
The ball's speed as it passes the window on its way down is 9.9 m/s
[tex]mgh=\dfrac{1}{2}mv^2\\\Rightarrow v=\sqrt{2gh}\\\Rightarrow v=\sqrt{2\times 9.81\times 25}\\\Rightarrow v=22.14723\ m/s[/tex]
The speed of impact on the ground is 22 m/s
