A ball is thrown horizontally from the top of a 20-m high hill. It strikes the ground at an angle of 45°. With what speed was it thrown?(adsbygoogle = window.adsbygoogle || []).push({});

I thought that we could use h=(Vi^2sin^2alpha)/2g. However, using that formula im not able to get to the correct answer which is 20m/s. What am I doing wrong?

Thanks!

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# Homework Help: Find the Speed of the ball

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