Bernoulli Equation: Finding t_fall Expression

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The discussion revolves around using the Bernoulli Equation to derive the exit velocity of a jet, expressed as V_o = √(2g(H-h)). The original poster is confused about how to find the time of fall (t_fall) using Bernoulli's principle. A participant clarifies that after finding V_o, the problem can be approached using basic projectile motion equations instead. The correct expression for t_fall is t = √(2h/g), simplifying the calculation process. The conversation emphasizes the distinction between applying Bernoulli's equation and using kinematic equations for projectile motion.
Saladsamurai
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Homework Statement



Picture3-16.png

Homework Equations



X=Vo*tfall

Bernoulli Eq: \frac {p}{\rho}+\frac{V^2}{2}+gz=const

I used B.E. to find an expression for the velocity of the exit jet:

V_o=\sqrt{2g(H-h)}

For some reason I am confused as to how to find an expression for t_fall ?

I know it should be easy, but I am under the impression I am supposed to use the B.E. to find it...

Any hints?
 
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Saladsamurai said:
I know it should be easy, but I am under the impression I am supposed to use the B.E. to find it...
That's not how I read the problem. You've used B.E. to find V0. The rest is just projectile motion.
 
Doc Al said:
That's not how I read the problem. You've used B.E. to find V0. The rest is just projectile motion.

Oh. Easy Enough then :smile:

Thanks again Doc!

t=sqrt(2h/g)
 
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