Select The Best Answer For The Question.1. If A Gas Has A Gauge Pressure Of 156 KPa, Its Absolute Pressure Is Approximately:A. 100 KPa B. 56 KPa C. 300 KPa D. 256 KPa

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Understanding Absolute Pressure: A Key Concept in Physics

In the field of physics, particularly in the study of gases and fluids, understanding pressure is crucial. Pressure is a measure of the force exerted per unit area on an object or surface. There are two types of pressure: gauge pressure and absolute pressure. Gauge pressure is the pressure measured relative to atmospheric pressure, while absolute pressure is the total pressure, including atmospheric pressure. In this article, we will explore the concept of absolute pressure and how to calculate it.

What is Absolute Pressure?

Absolute pressure is the total pressure exerted on an object or surface, including atmospheric pressure. It is the sum of the gauge pressure and atmospheric pressure. Atmospheric pressure is the pressure exerted by the weight of the air in the atmosphere. At sea level, atmospheric pressure is approximately 101.3 kPa.

Calculating Absolute Pressure

To calculate absolute pressure, we need to add the gauge pressure to the atmospheric pressure. The formula for calculating absolute pressure is:

Absolute Pressure = Gauge Pressure + Atmospheric Pressure

Example Problem

Let's consider an example problem to illustrate how to calculate absolute pressure. Suppose we have a gas with a gauge pressure of 156 kPa. We want to find its absolute pressure.

Step 1: Identify the Given Values

  • Gauge pressure: 156 kPa
  • Atmospheric pressure: 101.3 kPa

Step 2: Apply the Formula

Using the formula for calculating absolute pressure, we can plug in the values:

Absolute Pressure = 156 kPa + 101.3 kPa

Step 3: Calculate the Absolute Pressure

Performing the calculation, we get:

Absolute Pressure = 257.3 kPa

Rounding the Answer

Since the options are given in whole numbers, we can round the answer to the nearest whole number. In this case, we can round 257.3 kPa to 256 kPa.

Conclusion

In conclusion, absolute pressure is the total pressure exerted on an object or surface, including atmospheric pressure. To calculate absolute pressure, we need to add the gauge pressure to the atmospheric pressure. In the example problem, we calculated the absolute pressure of a gas with a gauge pressure of 156 kPa and found it to be approximately 256 kPa.

Selecting the Best Answer

Based on our calculation, the best answer for the question is:

D. 256 kPa

This answer is the closest to our calculated value of 257.3 kPa, which we rounded to 256 kPa.

Additional Tips and Resources

  • To learn more about pressure and its applications, check out online resources such as Khan Academy or Physics Classroom.
  • Practice calculating absolute pressure with different gauge pressures and atmospheric pressures to become more comfortable with the concept.
  • Remember to always round your answers to the nearest whole number when working with options in whole numbers.
    Absolute Pressure Q&A: Frequently Asked Questions

In our previous article, we explored the concept of absolute pressure and how to calculate it. However, we know that there are many more questions and topics related to absolute pressure that need to be addressed. In this article, we will provide answers to some of the most frequently asked questions about absolute pressure.

Q: What is the difference between gauge pressure and absolute pressure?

A: Gauge pressure is the pressure measured relative to atmospheric pressure, while absolute pressure is the total pressure, including atmospheric pressure. In other words, gauge pressure is the pressure exerted by a gas or fluid above atmospheric pressure, while absolute pressure is the total pressure, including atmospheric pressure.

Q: How do I calculate absolute pressure?

A: To calculate absolute pressure, you need to add the gauge pressure to the atmospheric pressure. The formula for calculating absolute pressure is:

Absolute Pressure = Gauge Pressure + Atmospheric Pressure

Q: What is atmospheric pressure?

A: Atmospheric pressure is the pressure exerted by the weight of the air in the atmosphere. At sea level, atmospheric pressure is approximately 101.3 kPa.

Q: Why is it important to consider atmospheric pressure when calculating absolute pressure?

A: Atmospheric pressure is an important factor to consider when calculating absolute pressure because it is a significant component of the total pressure. Ignoring atmospheric pressure can lead to inaccurate calculations and incorrect conclusions.

Q: Can I use a pressure gauge to measure absolute pressure?

A: No, a pressure gauge can only measure gauge pressure. To measure absolute pressure, you need to use a pressure gauge that is calibrated to measure absolute pressure or use a separate device to measure atmospheric pressure and then calculate the absolute pressure.

Q: What are some common applications of absolute pressure?

A: Absolute pressure is used in a variety of applications, including:

  • Aerospace engineering: Absolute pressure is used to calculate the pressure of gases and fluids in aircraft and spacecraft.
  • Chemical engineering: Absolute pressure is used to calculate the pressure of gases and fluids in chemical reactors and processing equipment.
  • Medical equipment: Absolute pressure is used to calculate the pressure of gases and fluids in medical equipment, such as ventilators and anesthesia machines.

Q: How do I convert gauge pressure to absolute pressure?

A: To convert gauge pressure to absolute pressure, you need to add the gauge pressure to the atmospheric pressure. The formula for converting gauge pressure to absolute pressure is:

Absolute Pressure = Gauge Pressure + Atmospheric Pressure

Q: Can I use a calculator to calculate absolute pressure?

A: Yes, you can use a calculator to calculate absolute pressure. Simply enter the gauge pressure and atmospheric pressure values into the calculator and use the formula:

Absolute Pressure = Gauge Pressure + Atmospheric Pressure

Conclusion

In conclusion, absolute pressure is an important concept in physics and engineering that requires a clear understanding of the relationship between gauge pressure and atmospheric pressure. By following the formulas and tips outlined in this article, you can calculate absolute pressure with confidence and accuracy.

Additional Resources

  • Khan Academy: Khan Academy offers a comprehensive course on physics, including a section on pressure and fluids.
  • Physics Classroom: The Physics Classroom website offers a detailed explanation of pressure and fluids, including a section on absolute pressure.
  • Engineering Toolbox: The Engineering Toolbox website offers a calculator for converting gauge pressure to absolute pressure.