Fluid Dynamics Homework: Solving for Water Speed and Range in a Container

AI Thread Summary
The discussion revolves around solving fluid dynamics homework involving a container with spouts at varying heights. The main focus is on calculating the speed of water exiting each spout and determining which stream has the greatest range. The initial attempt used Bernoulli's Equation but contained a critical error regarding the measurement of height differences in centimeters instead of meters. Once this mistake was corrected, the participant was able to arrive at the correct answer, aligning with the teacher's solution. The conversation highlights the importance of unit consistency in fluid dynamics calculations.
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Homework Statement



A container has spouts 10 cm, 20 cm, 30 cm, and 40 cm. The water level is maintained at a 45 cm height by an outside supply. (a) what is the speed of the water out of each hole? (b) which water stream has the greatest range relative to the base of the container?

Homework Equations



Bernoulli's Equation: p1 + 1/2desnityv12 + pgy1 = p2 + 1/2densityv22 + pgy2

The Attempt at a Solution



I tried to first solve the the spout 40 cm high. Using the equation, the pressure and density gets canceled, so we have:

v12 - v22 = 2g(y2 - y1)

since v2 = 0, then

v1 = square root of 2g(y2 - y1)

v1 = square root of 2(9.8)(45 - 40)
v1 = 9.9

But my answer is wrong according to my teacher... :( Hope you can help me
 
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azure2s said:

Homework Statement



A container has spouts 10 cm, 20 cm, 30 cm, and 40 cm. The water level is maintained at a 45 cm height by an outside supply. (a) what is the speed of the water out of each hole? (b) which water stream has the greatest range relative to the base of the container?

Homework Equations



Bernoulli's Equation: p1 + 1/2desnityv12 + pgy1 = p2 + 1/2densityv22 + pgy2

The Attempt at a Solution



I tried to first solve the the spout 40 cm high. Using the equation, the pressure and density gets canceled, so we have:

v12 - v22 = 2g(y2 - y1)

since v2 = 0, then

v1 = square root of 2g(y2 - y1)

v1 = square root of 2(9.8)(45 - 40)
v1 = 9.9

But my answer is wrong according to my teacher... :( Hope you can help me

Your height difference is measured in cm not m.
 
LowlyPion said:
Your height difference is measured in cm not m.

LOL! I can't believe that was the only mistake I did! Thank you very much! =)) Now my answer is the same with my teacher's.
 
azure2s said:
LOL! I can't believe that was the only mistake I did! Thank you very much! =)) Now my answer is the same with my teacher's.

Good luck.
 
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