(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A stone is thrown horizontally with an initial speed of 10 m/s from the edge of a cliff. 4.3 s later the stone hits the ground. What is the height of the cliff?

A swimmer heading directly across a river 200 m wide reaches the opposite bank in 6 min 40 s. She is swept downstream 480 m. How fast can she swim in still water?

2. Relevant equations

The problem here is that I don't understand why some equations are used sometimes...

3. The attempt at a solution

For example, for the first question, I just calculated 43 meters, since the speed is 10 meters per second. I am aware that the speed accelerate continuously, but I don't understand which equation to use.

For the second question, it's the same thing. I found 0.5 m/s.

Thanks for explaining where I am not thinking correctly. I know that my answers are not correct (well, pretty sure)..

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# Homework Help: Speed in still water/ throwing object horizontally.

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