The potential energy of a projectile at its maximum height is equal to its kinetic energy there . If the velocity of projection is 20m/s its time of flight is ?

2 answers

m g h = ½ m v²

h = v² / (2 g)

h = ½ g t² ... v² / (2 g) = ½ g t²

t = v / g .. this is ½ the flight time
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