Hello everyone. I've been at this for an hour now, so I think it's about time I asked for help.(adsbygoogle = window.adsbygoogle || []).push({});

We have a person on the surface of a planet with an unknown gravitational acceleration. The only measuring instrument available is a very accurate watch.

The person is on top of a cliff, and drops a rock from the top of it. It takes 4.15s for the rock to fall from the top of the cliff to the ground below. It travels X meters in total.

Afterwards, the person takes the rock, and throws it so that it travels up 2 meters above the top of the cliff, then it falls down to the ground. It travels (4 + X) meters in total Here is a simple depiction:

Case 1)

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Case 2:

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This shouldn't be that hard, but I'm still not getting it. Any help would be greatly appreciated. Thank you.

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# Confusing Kinematics and Acceleration

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