projectile

a projectile will cover the maximum vertical distance in the minimum time when the angle of its projection with the horizontal is

i know the ans is 45Â° but i am not able to prove it

2 Answers

karan the proof is relatively simple...

the time for which the projectile remains in the air is given by

2usinÎ¸/g

The horizontal velocity is u cosÎ¸

The range is horizontal velocity times "time"

so it is 2u²sinÎ¸.cosÎ¸/g

=u²sin2Î¸/g

for maxima sin 2Î¸=1

so Î¸=45 degreees :)

DIS ONE S A STD PROOF N SIMPLE TOO.....

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