Answer:
The velocity of watermelon when it passes Superman is 78 m/s.
Explanation:
Height of the building, d = 320 m
Speed of the superman, v = 39 m/s
We need to find the speed of watermelon when it passes Superman. Let t is the time taken by the watermelon. So,
[tex]d=ut+\dfrac{1}{2}gt^2[/tex]
Here u = 0
[tex]d=\dfrac{1}{2}gt^2[/tex]
[tex]39t=\dfrac{1}{2}\times 9.8\times t^2[/tex]
t = 7.95 seconds
Let v is the speed of the watermelon. It is given by :
[tex]v=gt[/tex]
[tex]v=9.8\times 7.95[/tex]
v = 77.91 m/s
or
v = 78 m/s
So, the velocity of watermelon when it passes Superman is 78 m/s.