A stone is DROPPED off a 144 foot cliff. A second later, another stone is THROWN off that cliff. The two hit the water at the same exact instant. What is the initial velocity of the second stone?(adsbygoogle = window.adsbygoogle || []).push({});

The answer is 40 ft/second according to my book, but for some reason, I never get that.

I set 4.9t^2 = v*(t-1) + 4.9(t-1)^2

I also set 144 = 4.9t^2 to get t = 5.421.

I plug this back into the first equation, and my answer comes out to 10.908 ft/ sec!

What am I doing wrong here?

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# Homework Help: Another aggravating kinematics problem - regarding stones

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