A 0.26 kg rock is thrown vertically upward from the top of a cliff that is 30 m high. When it hits the ground at the base of the cliff the rock has a speed of 25 m/s.(adsbygoogle = window.adsbygoogle || []).push({});

(a) Assuming that air resistance can be ignored, find the initial speed of the rock.

(b) Find the greatest height of the rock as measured from the base of the cliff.

I got part (a) to be 6.0 m/s, but do not know how to get part (b). If I know both velocities, what equation should I use to find max height? Thank you!

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# Homework Help: Rock Throwing

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