A person sitting on the top of a tall building is dropping balls at regular intervals of one second. Find the positions of the 3rd, 4th and 5th ball when the 6th ball is being dropped.

A person is releasing balls from a tall building at regular intervals of one second.
It means for each ball, the initial velocity u is 0.
Acceleration due to gravity, a = g = 9.8 m/s2


When the 6th ball is dropped, the 5th ball moves for 1 second, the 4th ball moves for 2 seconds and the 3rd ball moves for 3 seconds.



Position of the 3rd ball after t = 3 s:
Using the equation of motion, we get:



(from the top of the building)


Position of the 4th ball after t = 2 s:


(from the top of the building)


Position of the 5th ball after t = 1 s:



(from the top of the building)


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