Rotating cone filled with water

AI Thread Summary
The discussion revolves around determining the optimal position to drill a hole in a rotating cone filled with water to maximize the distance the water sprays. The user applies the Bernoulli equation to derive the velocity of water at the hole, considering factors like height and rotation. There is uncertainty about whether the Bernoulli equation is correctly applied, particularly regarding the incorporation of rotational velocity. The user also explores using Lagrange multipliers to solve the problem but struggles with the calculations. The conversation highlights the influence of cone shape on spray distance and the complexities of fluid dynamics in a rotating system.
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I have a cone filled with liqid with radius R and height H rotating with \omega. Where do we have to drill a hole that the water would spray to the maximum distance from the cone?

I used the Bernoulli equation obtainig
p_0+0.5 \rho {v_1}^2=p_0+0.5 \rho v^2
v is the speed at the hole, getting

v^2=2g(H-h-h^2-r^2\frac{\omega^2}{2g})=2g(H-h-h^2\frac{(tg{\alpha})^2}\omega^2}{2g}),
where tg{\alpha}=R/H.
I taught using Lagrange multiplicator, where the constraint is the water falling on the floor prom the upward cone:

\psi=v sin{\alpha} t+gt^2/2-h=0.

Further more:
F=v_x t+\lambda(v sin{\alpha} t+gt^2/2-h)
=v cos{\alpha}+\lambda(v sin{\alpha} t+gt^2/2-h)
Solution should be obtained by
\frac{\partial F}{partial t} and

\frac{\partial F}{partial v}, v=v(h),
but i can't solve it.
Did I make the concept wrong? Any ideas would be helpfull.

PS: The cone is standing on its tip and it is opened at the top.
 
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Two things will help to spray that water; the pressure which increases as we go down the cone, and the angular momentum which increases as we go up the cone. With a very flat cone I should imagine the best place is near the top; With a very sharp cone I guess the best place is near the bottom. There should be an angle at which it doesn't matter.
 
Thank you. I agree. But the problem is solving the equation. Is the use of Bernoulli eq. even correct. Do I incorporate the rotation velocity in Bernoulli eq. or as a separate contribution?
 
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