what is the aim of boyle's law experiment

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• Understanding Boyle's Law Experiment
• Physics experiments

In the world of physics, there are countless experiments that have helped us understand the laws of nature. One such experiment is Boyle's Law experiment, named after the Irish scientist Robert Boyle who conducted it in the 17th century. This experiment is a fundamental concept in thermodynamics and is essential for understanding the behavior of gases. It involves studying the relationship between the pressure and volume of a gas at constant temperature.

The results of this experiment have been crucial in advancing our understanding of how gases behave and have practical applications in various fields, from scuba diving to medical technology. In this article, we will delve deeper into Boyle's Law experiment, exploring its history, significance, and real-life applications. So, let's begin our journey into the fascinating world of physics experiments with a focus on thermodynamics. First, let's start with the basics. Boyle's Law is a gas law that describes the relationship between pressure and volume at a constant temperature.

It states that as the pressure of a gas increases, its volume decreases, and vice versa. This law was discovered by Irish chemist and physicist Robert Boyle in the 17th century and has since been a crucial concept in understanding the behavior of gases. Boyle's Law experiment is a simple yet effective way to demonstrate this law. The experiment involves a closed system with a fixed amount of gas at a constant temperature. By changing the pressure of the gas and measuring its corresponding volume, we can observe the inverse relationship between the two variables. One popular example of this experiment is using a syringe filled with air.

As we push down on the plunger, the pressure inside the syringe increases, causing the volume of air to decrease. This is because the increased pressure compresses the gas molecules, reducing the space they occupy. Another way to visualize Boyle's Law is by using a graph of pressure versus volume. The resulting curve is a hyperbola, with pressure and volume having an inverse relationship. This graph can also be used to calculate the constant value in Boyle's Law equation, PV = k.Now, you may be wondering why Boyle's Law is so important.

Well, it has many practical applications in our daily lives. For example, it helps explain how a balloon expands when we blow air into it, or how scuba divers use compressed air tanks to breathe underwater. In the field of thermodynamics, Boyle's Law is essential for understanding the behavior of gases in different systems. It also serves as a fundamental principle for other gas laws such as Charles' Law and Gay-Lussac's Law. In conclusion, Boyle's Law experiment is a crucial part of understanding the behavior of gases in various systems. Whether you are a student, researcher, or simply curious about physics experiments, this law is a fundamental concept that is worth exploring.

Understanding Boyle's Law

Conducting a boyle's law experiment, helpful tutorials and resources, careers in physics.

Whether you are interested in conducting research, teaching, or working in industry, a strong foundation in Boyle's Law will be essential in your career. Some of the fields of physics that you can pursue include astrophysics, particle physics, biophysics, and many more. Each field offers unique challenges and opportunities to contribute to our understanding of the universe. As a physicist, you can also work in a variety of industries such as aerospace, energy, and technology. These industries rely on the principles of physics to develop new technologies and improve existing ones. With the rapid advancements in technology, there is a high demand for skilled physicists in the job market. To get started on your career path in physics, it is important to have a strong understanding of fundamental concepts like Boyle's Law.

Solving Problems Using Boyle's Law

For example, if you have a fixed amount of gas in a container and you increase the pressure, the volume of the gas will decrease proportionally according to Boyle's Law. This relationship can be expressed mathematically as P1V1 = P2V2, where P1 and V1 are the initial pressure and volume, and P2 and V2 are the final pressure and volume. Another application of Boyle's Law is in determining the pressure of a gas at different volumes. For instance, if you have a gas in a container with a fixed volume and you decrease the volume, the pressure will increase according to Boyle's Law. This can be represented as P1V1 = P2V2, where P1 and V1 are the initial pressure and volume, and P2 and V2 are the final pressure and volume. By understanding how to apply Boyle's Law, you can solve various problems involving gases and their properties.

Latest Research in Boyle's Law

It states that as the volume of a gas decreases, the pressure increases proportionally. This law has numerous applications in industries such as chemistry, engineering, and medicine. In recent years, there have been several advancements in understanding Boyle's Law and its applications. One study published in the Journal of Chemical Education explored the use of Boyle's Law in determining the amount of carbon dioxide in soft drinks.

This research has implications for quality control in the beverage industry. Another study published in Physical Review Letters investigated the effects of Boyle's Law on quantum gases. The researchers found that at ultra-low temperatures, gases behave differently than predicted by classical Boyle's Law. This discovery has opened up new possibilities for understanding the behavior of matter at extremely low temperatures.

In recent years, there have been numerous studies conducted on Boyle's Law and its applications in various fields. Researchers have been able to apply this fundamental concept in thermodynamics to solve real-world problems and make significant advancements in different industries. One area where Boyle's Law has been extensively studied is in the field of gas dynamics. Scientists have been able to use this law to predict the behavior of gases at different temperatures and pressures, which has led to the development of more efficient engines and turbines. Another interesting application of Boyle's Law is in the medical field. By understanding how gases behave under different conditions, researchers have been able to develop better respiratory equipment and treatments for patients with respiratory illnesses. Furthermore, research on Boyle's Law has also led to a better understanding of the behavior of fluids in general.

Example Problem:

This includes the properties of gases and how they behave under different conditions. In simple terms, Boyle's Law states that the pressure of a gas is inversely proportional to its volume at a constant temperature. This means that if the volume of a gas decreases, its pressure will increase and vice versa. This law was first discovered by Irish scientist Robert Boyle in the 17th century during his experiments with air and the properties of gases.

In order to understand this law in depth, we must first understand the properties of gases. Unlike solids and liquids, gases have no definite shape or volume. They are able to expand and contract to fill the space available to them. The behavior of gases is governed by various physical laws and principles, one of which is Boyle's Law.

Now, let us delve deeper into the concept of pressure and volume in relation to gases. Pressure refers to the force exerted by a gas on the walls of its container. This force is a result of the collisions between gas molecules and the container walls. The volume of a gas, on the other hand, refers to the amount of space it occupies.

When we apply Boyle's Law to these two variables, we can see how they are inversely related. As the volume of a gas decreases, its molecules are pushed closer together, resulting in more frequent collisions with the container walls and therefore, an increase in pressure. Similarly, when the volume increases, there is more space for the molecules to move around, leading to fewer collisions and a decrease in pressure. Understanding these basic principles is crucial in comprehending Boyle's Law and its implications in thermodynamics experiments.

Another research

A more recent study.

Boyle's Law states that at a constant temperature, the volume of a gas is inversely proportional to its pressure. In simpler terms, as pressure increases, the volume decreases and vice versa. This means that we can use this relationship to solve for unknown variables in problems involving gases. For example, if we know the initial volume and pressure of a gas and want to find the final volume after a change in pressure, we can use Boyle's Law to calculate it.

Another practical application of Boyle's Law is in experiments involving gases. By manipulating the pressure and volume of a gas, we can observe the effects on other properties such as temperature and mass. This helps us understand the behavior of gases and their properties. Overall, understanding Boyle's Law is crucial for solving problems and conducting experiments related to gases and thermodynamics.

So whether you are a student, researcher, or simply curious about the world of physics, make sure to keep this law in mind!By now, you should have a solid understanding of Boyle's Law and how it relates to thermodynamics . Whether you are conducting an experiment or using it to solve problems, this law is a fundamental concept that is crucial to grasp. Keep exploring and learning about the exciting world of physics !.

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Experiment 2 - Boyles Law

Electrical & electronics 1 (elec6010), cork institute of technology.

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Preview text

Experiment 2 – boyles law.

Introduction:

The behaviour of a gas in an enclosed vessel can be described by four variables of pressure P , volume V , temperature T and the number of molecules n contained in the vessel. These variables are related to each other as shown in the ideal gas law equation below...

where k is Boltzmann’s constant.

The apparatus consists of a glass tube filled with red oil, which has trapped a small quantity of air. The tube can be attached to the laboratory air supply line via a valve, which can be open and closed. In this experiment, you will investigate how the volume of trapped air changes when the applied pressure is changed.

• With the apparatus disconnected from the airline, open the valve at the Bourdon gauge -record the initial pressure on the gauge and height of the oil.
• Close the valve at the Bourdon gauge and connect to the airline.
• Open the valve slowly and let the pressure increase up to about 2 × 105Pa.
• Close the valve fully and disconnect from the airline.
• Wait for a few minutes to ensure the temperature of the trapped air is at room temperature (compressing a gas tends to cause heating) then record the value of the volume (cm3) and the value of pressure (Pa).
• Open the Bourdon gauge valve slightly to reduce the applied pressure, wait a minute for temperature to return to its original value and record new values for volume and pressure.
• Repeat procedure until you have ten values of volume making sure your values are reasonably spread out.
• Estimate the error on your measurements of P by repeating one of your measurements so that you get the same volume. The difference between your values of P can be taken as your estimate of the error P.
• Plot a graph in Excel of P on the y-axis and 1/Von the x-axis.
• Use Excel to place a line of best fit and equation of the line on your data.
• The value of the intercept should equal atmospheric pressure. Comment on your value for atmospheric pressure.

Controlled Variables

 Temperature is controlled by waiting for the gas to reach room temperature before making each measurement.  The mass of gas is kept constant as it is in a sealed container.

Pressure Volume 1/Volume 2 15 0. 2 16 0. 2 18 0. 1 20 0. 1 23 0. 1 26 0. 1 30 0. 1 37 0.

0 0 0 0 0 0 0 0 0.

Conclusion:

In our experiment, our results firmly supported Boyle’s law. We found that a decrease in volume will increase pressure. In addition, multiplying temperature by pressure gave us values that were all very similar to each other. As a result, our results show us that the change in pressure and volume, while an inverse relationship, is nearly linear. Overall, this experiment reaffirmed that a decrease in volume causes an increase in pressure.

Precautions:

 Allow time for the gas to reach room temperature before making each measurement.  Read the volume from the bottom of the meniscus.

Sources of Error:

• Multiple Choice

Module : Electrical & Electronics 1 (ELEC6010)

University : cork institute of technology.

Boyles Law Experiment

• Practice Questions

Boyle’s Law Experiment demonstrates the relationship between the pressure and volume of a gas, as stated in Boyle’s Law – the pressure of a gas is inversely proportional to its volume when temperature and the amount of gas remain constant. In other words, as the volume decreases, the pressure increases, and vice versa.

What is Boyles Law Experiment?

Boyle’s law experiment theory.

The theory behind the Boyle’s Law Experiment is rooted in the principles of gas behavior under constant temperature conditions. Boyle’s Law is one of the fundamental gas laws that describe the relationship between the pressure and volume of a gas. The law asserts that the pressure of a given amount of gas is inversely proportional to its volume, provided the temperature remains constant.

Inverse Relationship : Boyle’s Law states that as the volume of a gas decreases. Its pressure increases, and vice versa, assuming a constant temperature. This relationship is mathematically expressed as:

• P is the pressure of the gas,
• V is its volume.

Molecular Theory : According to the kinetic theory of gases, gas molecules move rapidly and collide with the container walls, creating pressure. When the gas volume decreases, the gas molecules have less space to move around, causing more frequent collisions with the container walls. Which results in increased pressure.

Isothermal Process : In an isothermal process, the experiment maintains a constant temperature during volume changes. This process keeps the gas’s internal energy the same. Ensuring that the pressure-volume relationship remains inversely proportional.

Procedure of Boyle’s Law Experiment

• Connect a syringe to a pressure gauge or manometer, ensuring an airtight seal.
• Alternatively, use a piston-cylinder assembly with a pressure measuring device.

Initial Measurement :

• Set the syringe or piston to a specific volume and record the initial pressure reading from the gauge or manometer.

Change Volume :

• Gradually alter the gas volume by moving the syringe plunger or piston.
• For compression, push the plunger inward or add weight to the piston. For expansion, pull the plunger outward or remove weight from the piston.

Record Pressure :

• At each volume change, measure and note the corresponding pressure.

Repeat and Gather Data :

• Continue adjusting the volume in increments, each time recording the pressure.
• Repeat multiple times to obtain a wide range of data points.

Plot Data :

• Plot the recorded pressure values against the inverse of the volume (1/V).
• The graph should show a linear relationship if Boyle’s Law holds true.
• Analyze the graph to confirm the inverse relationship between pressure and volume.
• Verify that the pressure increases as the volume decreases and vice versa, demonstrating Boyle’s Law.

FAQ’S

What is boyle’s law.

Boyle’s Law states that at constant temperature, the pressure of a gas is inversely proportional to its volume. If one increases, the other decreases.

Why is the Boyle’s Law experiment important?

It helps us understand gas behavior under varying pressures and volumes, which is essential in designing equipment like syringes, pneumatic systems, and respiratory devices.

How does temperature affect the Boyle’s Law experiment?

The experiment requires a constant temperature. Fluctuating temperatures introduce variables that disrupt the inverse relationship between pressure and volume.

What equipment is needed for the experiment?

A sealed syringe or piston-cylinder assembly, a pressure gauge or manometer, and a setup that allows for accurate volume adjustments and pressure measurements.

How do you ensure the system is airtight?

Use well-fitted, sealed connections and test for leaks by applying soapy water to joints and looking for bubbles when pressure is applied.

How does the pressure change with volume?

As the volume decreases, the gas molecules collide more frequently, increasing pressure. Expanding the volume reduces collisions, decreasing pressure.

What graph should the data produce?

A graph plotting pressure against the inverse of volume (1/V) should yield a straight line if the data aligns with Boyle’s Law.

Can Boyle’s Law apply to liquids or solids?

No, Boyle’s Law specifically applies to gases because of their compressibility. Liquids and solids don’t change volume significantly under pressure.

What are some real-world applications of Boyle’s Law?

It is used in scuba diving, automobile engines, and medical devices like syringes and ventilators, where controlling gas pressure and volume is crucial.

How does the Boyle’s Law experiment demonstrate an isothermal process?

By maintaining constant temperature during volume changes, the experiment demonstrates an isothermal process where internal energy remains stable, proving the inverse pressure-volume relationship.

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Experiment Boyle’s Law: Pressure-Volume Relationship in Gases Experiments​

Boyle’s law: pressure-volume relationship in gases.

Experiment #6 from Chemistry with Vernier

Video Overview

Introduction

The primary objective of this experiment is to determine the relationship between the pressure and volume of a confined gas. The gas we use will be air, and it will be confined in a syringe connected to a Gas Pressure Sensor. When the volume of the syringe is changed by moving the piston, a change occurs in the pressure exerted by the confined gas. This pressure change will be monitored using a Gas Pressure Sensor. It is assumed that temperature will be constant throughout the experiment. Pressure and volume data pairs will be collected during this experiment and then analyzed. From the data and graph, you should be able to determine what kind of mathematical relationship exists between the pressure and volume of the confined gas. Historically, this relationship was first established by Robert Boyle in 1662 and has since been known as Boyle’s law.

In this experiment, you will

• Use a Gas Pressure Sensor and a gas syringe to measure the pressure of an air sample at several different volumes.
• Determine the relationship between pressure and volume of the gas.
• Describe the relationship between gas pressure and volume in a mathematical equation.
• Use the results to predict the pressure at other volumes.

Sensors and Equipment

This experiment features the following sensors and equipment. Additional equipment may be required.

Correlations

Teaching to an educational standard? This experiment supports the standards below.

Ready to Experiment?

Ask an expert.

Get answers to your questions about how to teach this experiment with our support team.

• Call toll-free: 888-837-6437
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Purchase the Lab Book

This experiment is #6 of Chemistry with Vernier . The experiment in the book includes student instructions as well as instructor information for set up, helpful hints, and sample graphs and data.

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Boyle’s Law and the Law of Atmospheres

Michael Fowler, UVa 

Introduction

We’ve discussed the concept of pressure in the previous lecture, introduced units of pressure (Newtons per square meter, or Pascals, and the more familiar pounds per square inch) and noted that a fluid in a container exerts pressure on all the walls, vertical as well as horizontal — if a bit of wall is removed, the fluid will squirt out. 

Everyone knows that although water (like other liquids) is pretty much incompressible, air is compressible — you can squeeze a small balloon to a noticeably smaller volume with your hands, and you can push in a bicycle pump to some extent even if you block the end so no air escapes.  . Boyle was the first person to make a quantitative measurement of how the volume of a fixed amount of air went down as the pressure increased.

One might imagine doing the experiment with gas in a cylinder as in the diagram here, putting on different weights and measuring the volume of the gas.  Once the piston is at rest, the pressure of the gas multiplied by the area of the piston would just balance the weight of the piston plus the added weight, so the pressure is easy to find.

But there is one tricky point here: if the gas is compressed fairly rapidly — such as by adding a substantial weight, so the piston goes down suddenly — the gas heats up.  Then, as the heat escapes gradually through the walls of the cylinder, the gas gradually settles into an even smaller volume.

Boyle’s idea was to find out how the volume of the gas varied with outside pressure if the temperature of the gas stayed the same .  So, if he’d done his experiment with the cylinder pictured above, he would have had to wait quite a time between volume measurements to be sure the gas was back to room temperature.

But Boyle didn’t use a piston and cylinder.  He did the experiment in 1662.  Possibly the gun barrels manufactured at the time would have worked, with a greasy piston (I’m not sure) but he found a very elegant alternative: he trapped the air using mercury in a closed glass tube, and varied the pressure as explained below (in his own words).

He found a simple result : if the pressure was doubled, at constant temperature, the gas shrank to half its previous volume. If the pressure was tripled, it went to one-third the original volume, and so on.  That is, for pressure P and volume V , at constant temperature T ,   PV = constant.  This is Boyle’s Law .

After reviewing Boyle’s ingenious experiment, we shall see how Boyle’s Law is the key to understanding a central feature of the earth’s atmosphere: just how the density and pressure of air decreases with altitude.  Of course, the temperature of the atmosphere also varies with height and weather, complicating the picture, but Boyle’s law gives us a very good start in analyzing the situation.

Boyle’s Experiment

( See diagram below )

Robert Boyle was born on 1627, the fourteenth child of the Earl of Cork, an Irish landowner.

He wrote the account below in 1662. (It is from his book A Defense of the Doctrine Touching the Spring and Weight of the Air . I’ve added some notes in square brackets, which I hope clarify what’s going on.  Regular brackets, (  ), are Boyle’s own.)

“We took then a long glass-tube, which, by a dexterous hand and the help of a lamp, [ heating it so it softens ] was in such a manner crooked at the bottom, that the part turned up was almost parallel to the rest of the tube [ they bent it into the shape in the diagram ] and the orifice of this shorter leg of the siphon (if I may so call the whole instrument) being hermetically sealed, the length of it was divided into inches (each of which was subdivided into eight parts) by a streight list of paper, which containing those divisions was carefully pasted all along it.  Then putting in as much quicksilver as served to fill the arch or bended part of the siphon, that the mercury standing in a level might reach in the one leg to the bottom of the divided paper, and just to the same height of horizontal line in the other; we took care, by frequently inclining the tube, so that the air might freely pass from one leg into the other by the sides of the mercury (we took, I say, care) that the air at last included in the shorter cylinder should be of the same laxity with the rest of the air about it. [ He means at the same pressure, that is, the normal atmospheric pressure .]

This done, we began to pour quicksilver into the longer leg of the siphon, which by its weight pressing up that in the shorter leg, did by degrees streighten [compress] the included air: and continuing this pouring in of quicksilver till the air in the shorter leg was by condensation reduced to take up by half the space it possessed before; we cast our eyes upon the longer leg of the glass, on which was likewise pasted a list of paper carefully divided into inches and parts, and we observed, not without delight and satisfaction, that the quicksilver in that longer part of the tube was twenty-nine inches higher than the other.” 

Boyle’s “delight and satisfaction” in that last sentence arose because he knew that the extra pressure exerted by the added twenty-nine inches of mercury was equal to an extra atmosphere, so the air trapped in the shorter tube had halved in volume when the pressure was doubled .  He went on the repeat the experiment many times, with different heights of the column of mercury in the longer tube, and checking each day on the actual atmospheric pressure at the time of the experiment.  

He established Boyle’s Law,

for the range of pressures he used.  It is important to note that in his experiments he allowed a long enough time between volume measurements for the trapped air to get back to room temperature.

The Law of Atmospheres: An Ocean of Water

First, a quick reminder of how we found the pressure variation with depth in an ocean of water at rest.  We imagine isolating a small cylinder of water, with its axis vertical, and construct a free body diagram:  

The pressure forces from the surrounding water acting on the curved sides obviously all cancel each other.  So the only forces that count are the weight of the cylinder of water, and the pressure forces on the top and the bottom — that on the bottom being greater, since it must balance the pressure on the top plus the weight, since the cylinder is at rest.

Taking the cylinder to have cross-section area A ,  height Δ h ,  and the water to have density ρ ,  the cylinder has volume A Δ h ,  mass ρ A Δ h ,  and therefore weight   ρ A Δ h g .   

The pressure P  is a function of height h  above the bottom, P = P ( h ) .

We’ve measured h  here from the bottom of the ocean, because in the next section, we’ll apply the same analysis to the atmosphere, where we do live at the bottom of the “sea”.

The pressure on top of the cylinder exerts a downward force equal to

pressure × area = P ( h + Δ h ) A ,

the bottom feels an upward pressure P ( h ) A , , so since the total force must be zero,

P ( h + Δ h ) A − P ( h ) A + ρ A Δ h g = 0. .

This equation can be rearranged to:

P ( h + Δ h ) − P ( h ) Δ h = − ρ g .

Recalling that the differential is defined by d f ( x ) d x = lim Δ x → 0 f ( x + Δ x ) − f ( x ) Δ x ,  we see that this pressure equation in the limit Δ h → 0  becomes:

d P ( h ) / d h = − ρ g . .

Since ρ g  is a constant, the solution is simple:

P ( h ) = − ρ g ( h − h 0 )

where we’ve written the constant of integration in the form ρ g h 0 .   Notice the pressure in this ocean drops to zero at height h = h 0   — obviously the surface!  This means our formula describes water pressure in an ocean of depth h 0 ,  and is just a different way of writing that the pressure is ρ g  times the depth below the surface. (We are subtracting off the atmospheric pressure acting down on the ocean’s surface from the air above it — we’re just considering the extra pressure from the weight of the water itself as we descend.  Remember air pressure is the same as approximately thirty feet of water, so is a small correction in a real ocean)

An Ocean of Air

We now go through exactly the same argument for an “ocean of air”, drawing the same free body diagram for a small vertical cylinder, and arriving at the same differential equation,

d P ( h ) / d h = − ρ g .

But it doesn’t have the same solution!  The reason is that ρ ,  which we took to be constant for water (an excellent approximation), is obviously not constant for air.  It is well known that the air thins out with increasing altitude. 

The key to solving this equation is Boyle’s Law: for a given quantity of gas, it has the form P V = const .,  but notice that means that if the pressure of the gas is doubled, the gas is compressed into half the space, so its density is also doubled . 

So an alternative way to state Boyles law is

ρ ( h ) = C P ( h )

where C  is a constant (assuming constant temperature).  Putting this in the differential equation:

d P ( h ) / d h = − C P ( h ) g .

This equation can be solved (if this is news to you, see the footnote at end of this section):

P ( h ) = P 0 e − C g h .

The air density decreases exponentially with height: this equation is the Law of Atmospheres .

This density decrease doesn’t happen with water because water is practically incompressible. One analogy is to imagine the water to be like a tower of bricks, one on top of the other, and the air a tower of brick-shaped sponges, so the sponges at the bottom are squashed into much greater density — but this isn’t quite accurate, because at the top of the atmosphere, the air gets thinner and thinner without limit, unlike the sponges.

Footnote: Solving the Differential Equation

The equation is the same as d f ( x ) d x = a f ( x ) ,  where a  is a constant. If you are already familiar with the exponential function, and know that d d x e a x = a e a x ,  you can see the equation is solved by the exponential function.  Otherwise, the equation can be rearranged to d f f = a d x ,  then integrated using ∫ d f f = ln f  to give ln f ( x ) = a x + c ,  with c  a constant of integration. Finally, taking the exponential of each side, using e ln f ( x ) = f ( x ) ,  gives f ( x ) = C e a x ,  where C = e c .

1.  Atmospheric pressure varies from day to day, but 1 atm is defined as 1.01 x 10 5 Pa.  Calculate how far upwards such a pressure would force a column of water in a “water barometer”.

2.  The density of air at room temperature is about 1.29 kg/m 3 .  Use this together with the definition of 1 atm above to find the constant C  in the Law of Atmospheres written above. Use your result to estimate the atmospheric pressure on top of the Blue Ridge (say 4000 feet), Snowmass (11,000 feet) and Mount Everest (29,000 feet).

3.  As a practical matter, how would you measure the density of air in a room?  Actually, Galileo did this in the early 1600’s. Can you figure out how he managed to do it?  (His result was off by a factor of two, but that was still pretty good!)