A rock is thrown off a 100.0m cliff upward at an angle of 20(adsbygoogle = window.adsbygoogle || []).push({}); ^{o}to the horizontal. It has an initial velocity of 15ms^{-1}and strikes the rocks below.

Find how far away the rock is from the base of the cliff.

I calculated total time of flight (projectile parabola + 100m vertical descent) which equalled around 4.3-5.0 (verified by textbook.)

The total time of flight for the parabolic section was about 1.046s

Horizontal component= 15cos20 = 14.095ms^{-1}

S_{H}= ut = 14.095 x 1.046 = 14.74m.

However, the answer is 70m and you can only acquire that by 14.095 x 5 which doesn't make sense because I thought after being projected at an angle it would make a completely vertical descent thus having no effect whatsoever on the horizontal component.

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# Homework Help: Projectile Motion - Horizontal Component

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