   # A ball is thrown upwards with speed v from the top of a tower and its reaches...........What is the height of the tower?

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A ball is thrown upwards with speed v from the top of a tower and its reaches the ground with speed 3v.
What is the height of the tower? posted Nov 5, 2019

Height of the tower = h m
Initial velocity (u) = v m/s
Final velocity (v) = -3v m/s
Using Newton's third equation of motion : v² - u² =2as --> (3v)² - v² = 2*(-g)(-h) --> h = 4v²/g m answer Nov 5, 2019

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