Calculating Water Velocity Using Bernoulli's Equation

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Homework Help Overview

The discussion revolves around calculating the velocity of water exiting an opening using Bernoulli's equation, and further exploring related questions about the motion of the water after it exits, including time to hit the ground, horizontal distance, and acceleration due to gravity.

Discussion Character

  • Exploratory, Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants discuss the application of Bernoulli's equation and question the use of conservation of energy and momentum in this context. They also consider the relevance of kinematic equations for analyzing the motion of the water after it exits the opening.

Discussion Status

Some participants have provided guidance on using conservation laws and kinematic equations, while others are exploring the implications of gravity on momentum conservation. There is an acknowledgment of missing visual context, which may affect the discussion.

Contextual Notes

Participants note the absence of a diagram initially, which is crucial for understanding the setup. There are also questions about specific values and parameters, such as the height (H) and the initial geometry of the setup.

Gamma
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The velocity of the water that comes out of the opening in the attached diagram can be found using Bernoulli equation, as

v = sqrt (2gh)

Once the water exits the hole, I am not sure how to answer questions like the following: Can I use conservation of energy and momentum. Also can I use the equations in kinematics (ie. S = ut + 1/2 a t^2, v=u+at,...)

1. Time for the water to hit the ground,
2. What is the value of H
3. What is the horizontal distance of flight of water
4. What is the acceleration ( acce. of gravity??)


Thanks a lot.

Gamma.
 

Attachments

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Usually the kinematic equations are all you need assuming you know the initial geometry of the set up. I see no picture, so I can't tell.
 
Yes the pic did not show up. It is there now. Sorry.
 
How about conservation of energy and momentum? I can cosider a mass of water that exits the hole per unit time as 'm' and write the conservation lows. Is seems ok to do that.

edit: May be momentum is not conserved in the vertical direction due to the force of gravity.?
 
Last edited:
You could use conservation laws also, I presume
 

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