Hello, I would appreciate any help!(adsbygoogle = window.adsbygoogle || []).push({});

1. The problem statement, all variables and given/known data

A river narrows at a rapids from a width of 12m to a width of only 5.8m. The depth of the river before the rapids is 2.7m; the depth in the rapids is .85m. Find the speed of water flowing in the rapids, given that its speed before the rapids is 1.2m/s. Assume the river has a rectangular cross section.

2. Relevant equations

I'm using bernoulli's equation:

P1+pv^2/2+pgy=P2+pv2^2+pgy2

and P=F/A

3. The attempt at a solution

I figured I would have to find the Pressures at the top and the bottom with P=F/A. The area I can find with the depth and width given but how do I find the force. Or is the pressure on the top of the river just atmospheric pressure?

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# Homework Help: Speed of Water Flowing

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