| 1E-2 : | Pressure Gage and Manometer Readings | 6 pts |
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| A cylindrical tank contains pressurized nitrogen gas. The gage on the tank reads 88 kPa. A manometer is attached to the tank to verify its pressure. Determine the manometer reading in cm if the manometer fluid is … | ||||||||||||||
| a.) ρmercury = 13,600 kg/m3, b.) ρwater = 1000 kg/m3 | ||||||||||||||
| Read: | Remember that gage pressure is the difference between the absolute pressure and atmospheric pressure. | |||||||||||||
| Apply the Barometer Equation with a known gage pressure to determine the manometer reading, h. | ||||||||||||||
| Given: | Pgage | 88 | kPa | |||||||||||
| rw | 1000 | kg/m3 | ||||||||||||
| rHg | 13600 | kg/m3 | ||||||||||||
| Find: | h | ??? | m | |||||||||||
| Assumptions: | 1- The nitrogen and water in the system are completely static. | |||||||||||||
| 2- The densities of the nitrogen and water are uniform and constant. | ||||||||||||||
| 3- The acceleration of gravity is: | g | 9.8066 | m/s2 | |||||||||||
| gC | 1 | kg-m/N-s2 | ||||||||||||
| Equations / Data / Solve: | ||||||||||||||
| Gage pressure is defined by : |
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Eqn 1 | ||||||||||||
| The Manometer Equation tells us that : | 
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Eqn 2 | ||||||||||||
| Combining Eqns 1 & 2 gives us : |
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Eqn 3 | ||||||||||||
| Now, we can solve Eqn 3 for h : |
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Eqn 4 | ||||||||||||
| Now, we can plug values into Eqn 4 : | a.) | h | 0.660 | m | ||||||||||
| b.) | h | 8.974 | m | |||||||||||
| Answers: | a.) | h | 0.66 | m | ||||||||||
| b.) | h | 8.97 | m | |||||||||||
