Question #40610

1 Answer
Jan 21, 2017

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As referred to the figure above.

Kinetic energy at point of projection KEprojection=12mu2
Maximum height of the object having mass m will be reached when sinθ component of projectile's velocity becomes 0 (zero).

As such kinetic energy at this point is given by
KEmax height=12m(ucosθ)2
Ratio of the two is KEmax heightKEprojection=12m(ucosθ)212mu2
=cos2θ