Measuring the pressure of a gas

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SUMMARY

The discussion centers on the measurement of gas pressure, specifically addressing the pressure difference of 1000 pascals. It clarifies that when calculating the total pressure of a gas, one must consider both the pressure difference and atmospheric pressure, resulting in an absolute pressure of 101,000 pascals. The conversation emphasizes the importance of distinguishing between gauge pressure and absolute pressure in gas law applications, asserting that absolute pressure is the standard for calculations.

PREREQUISITES
  • Understanding of gauge pressure vs. absolute pressure
  • Familiarity with the concept of atmospheric pressure (101,000 pascals)
  • Basic knowledge of gas laws
  • Ability to interpret pressure measurements in scientific contexts
NEXT STEPS
  • Study the Ideal Gas Law and its applications
  • Learn about the differences between gauge pressure and absolute pressure
  • Explore the implications of pressure measurements in fluid dynamics
  • Investigate how atmospheric pressure affects various gas behaviors
USEFUL FOR

Students in physics or chemistry, engineers working with gas systems, and anyone involved in scientific measurement and analysis of gas pressures.

Steve143
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http://img526.imageshack.us/img526/8780/pressurew.jpg

I worked out that the pressure difference is 1000 pascals

For part b the book says the pressure of the gas is 1000 pascals but shouldn't it be 1000 pascals + 100,000 pascals (atmospheric pressure) making the pressure of the gas 101,000 pascals? because the water has atmospheric pressure on it from the left side of the tube and the gas is not only counteracting it but pushing the water too making me think it is pressure difference + atmospheric pressure. I can't think of a reason why atmospheric pressure would be ignored and it would be stated as 1000
 
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When asked for the pressure it usually means the pressure disregarding atmospheric pressure. If atmospheric pressure is included it is called 'Absolute pressure' of the gas.
When dealing with the gas laws you must use the Absolute pressure.
So you are correct in some applications.
 
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