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

A soccer player kicks a rock horizontally off a 40.0 m high cliff into a pool of water. If the player hears the sound of the splash 3.07 s later, what was the initial speed given to the rock? Assume the speed of sound in air to be 343 m/s.

3. The attempt at a solution

So here is what I did. I first figured out the time it takes for the rock to hit the water by using the equation.

\frac{1}{2}gt^2 = 40

And I got 2.85714 s. From there I subtracted that number from the original time of 3.07 s to get .21286 s, which is the time for speed of sound to reach the top again. I them found the hyp distance by taking (.21286)(343) = 73.011 m

After that I drew a triangle with 73.011 m as the hyp. But now I'm stuck. I don't know how to still get the initial speed of the rock. I'm not even sure what equation I should use.

Please Help.

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# Homework Help: Stuck on a velocity problem, need some help

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