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azure2s
Sep29-08, 11:54 AM
1. The problem statement, all variables and given/known data

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?

2. Relevant equations

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

3. 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

LowlyPion
Sep29-08, 12:42 PM
1. The problem statement, all variables and given/known data

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?

2. Relevant equations

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

3. 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.

azure2s
Sep29-08, 12:54 PM
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.

LowlyPion
Sep29-08, 12:56 PM
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.