the relationship between cloud chambers, alpha particles

Sophie Reeves Colorado Science and Engineering Fair

April 79, 2016 Technical Writing Paper

The Relationship between Cloud Chambers, Alpha Particles,

Radon222, and Different Floors of a House

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Table of Contents

Contents:

1. Introduction………………………………………………………………………………………………..4 Figure 1….…………………………………………………………………………………………...5 2. Materials and Methods………………………………………………………………………......................6

Figure 2….…………………………………………………………………………………………...6 Figure 3…...…………………………………………………………………………….....................8

3. Results and Data Analysis………………………………………………………………………………....9 Table 1….…...…………………………………………………………………………......................9

Table 2…..…...…………………………………………………………………………………….…9 Table 3….....…………...…………………………………………………………………………....10 Table 4…..…...……………………………………………………………………...……………....10 Table 5….……………………………………………………………………………………….…..10 Table 6...………………………………………………………………………………………….…10 Figure 4….…………………………………………………………………………………………..11 Table 7…...……………………………………………………………………………………….....12 Figure 5….…………………………………………………………………………………………..12

4. Discussion of Results………………………………………………………………………………….….13 Summary of Data and Results……………………………………………………………………….....13 Error Analysis…………………………………………………………………………..........................14

Figure 6...………………………………………………………………………...………...14 Figure 7…....…………………………………………………………………………...…..14

Comparison of Findings………………………………………………………………………………...15 Next Steps……………………………………………………………………………………………....15 5. Conclusion……………………………………………………………………………………………......16 Acknowledgements………………………………………………………………………………….……...17 Works Cited………………………………………………………………………………………….……..18 Appendix A………………………………………………………………………………………….………20 Appendix B………………………………………………………………………………………….……....27 Appendix C………………………………………………………………………………………….……....34

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1. Introduction

Radon222, simply known as ‘radon’, is a naturally occurring, radioactive, colorless, odorless, noble gas that is produced from the decay of radium226 and originally uranium238 (“Radon in Colorado”). Radon is a considerable health hazard when in high quantities indoors, as large consumption of the gas can lead to lung cancer. According to the Environmental Protection Agency, most standard houses in the state of Colorado contain unsafe amounts of this gas, reaching an average of about 4 picoCuries per Liter (pCi/L) when there is no radon reduction (mitigation) system in place (“Find Information…”). Radon builds to higher concentrations inside homes than outside because it is more difficult for the gas to disperse (National Research Council Staff), thus mitigation systems are needed in most homes. Because radon amounts vary from home to home due to structure and foundation, a radon test is typically required, yet these radon tests usually take ninety days or more to complete ("Home Buyer's and Seller's Guide to Radon"). This process can be done in a much quicker and expedient way, with the use of a type of particle detector known as a cloud chamber, in which subatomic particles can be indirectly viewed. When radon decays into polonium218 ("What are the Radon Progeny?”), it commonly spits out alpha particles, subatomic particles made up of two protons plus two neutrons, (Venton), and the tracks that these alpha particle leave can be visible in a cloud chamber as well. By measuring the count of alpha particles, one can indirectly get a read for the radon levels in his/her house and can also determine what floor of the house has the highest radon count, thus determining for his/herself the right spot in the house to place the mitigation system. Because it comes from uranium in the soil, radon primarily finds its way into the basements of houses (Galen 180) and disperses as it travels upwards to the rest of the house. Hence, there will be a consistently higher count in the basement of a house than the top floor, so a cloud chamber will detect a greater count of alpha particles in the basement. This process will allow homeowners to ensure that the basement or lowest floor of their house is the right place to put a mitigation system in their homes.

Six houses were chosen in this experiment – three of them with shale as the underlying rock type and three of them with colluvium as the underlying rock type. Colluvium is an array of different rocks and soils accumulated at the base of a hill or slope (“Colluvium”). Shale is a soft rock that can split evenly into pieces, and often contains a wide array of minerals (“Shale”). Shale is known as Kpu, and colluvium as Qc. This can be viewed in Figure 1 below.

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Figure 1

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2. Materials and Methods

A small fish tank was used in the creation of the cloud chamber. A piece of felt was cut to be the same size as the bottom of the fish tank. A quartersize hole was cut in the middle of the felt, and it was hotglued to the bottom. The safety goggles and heavy gloves for handling dry ice were put on. A large bundle of black felt was folded to size and placed in the 18” by 14” base bucket, and eight pounds of icecube shaped dry ice were evenly scattered on top of the folded felt. The black aluminium sheet was placed on top of the dry ice. The sheet made a screeching noise for about fifteen seconds as it cooled down and adjusted to the temperature of the dry ice (78.5º C). The felt was soaked with 2 fl. oz of 99.957% purity isopropyl alcohol. When the isopropyl alcohol was done being used, the lid was closed tight and put in a safe place. The fish tank was put on top of the sheet with the side with the black felt towards the ceiling. An iPhone was placed on the top of the fish tank, and a wideangle lens was attached to it. The camera was placed so that the lens was looking through the quartersized hole. A halfinch block of material was placed on top of the fish tank so that the iPhone was resting on it and the camera was looking straight down into the tank. Another halfinch block of material was placed on the side of the metal plate. A flashlight was put on top of the block so that it is shining directly into the fish tank.

Figure 2

Figure 2 shows both the initial setup of the experiment and the view of the fish tank by the iPhone through the quartersized hole.

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For all houses that were tested, the fish tank was placed in a room with no windows. After setup, fifteen minutes elapsed before the experiment was continued. After fifteen minutes, the lights were turned off, and flashlight was turned on. The iPhone was also turned on and it recorded through the quartersized hole for 30 seconds. After thirty 30 seconds, the video was stopped. The iPhone was then turned back on and recorded for 60 seconds. After 60 seconds, the video was stopped. The iPhone was again turned back on and recorded for 90 seconds. The entire process was repeated for each floor of the house five times. After all of the data was gathered for one floor, the cloud chamber was carefully carried to the next. When the chamber was placed in the desired area, it sat for ten minutes before the experiment proceeded any further. Doing so allowed the carbon dioxide to resettle.

When all data was collected, the videos were downloaded in chronological order onto a computer and were put onto iMovie, a program that has a slowmotion feature. The number of bright, thick trails that were seen were counted. These are the alpha particles. The data charts were filled in for each time period of each trial. All items were disposed of properly, including the dry ice, which was was put back in the box in came in once finished with it so that it could sublimate naturally into a gas. Other Methods:

When cosmic rays hit Earth’s atmosphere, a shower of secondary particles are released. These secondary particles bombard humans every second. They are so small and fast, however, that they cannot be directly viewed (What are Cosmic Rays?). A cloud chamber is a type of device that can detect the trails that these particles leave. When the dry ice from the bottom of the detector travels upward and the isopropyl alcohol from the top of the detector travels downwards, the two create supersaturated vapor through which the particles pass. When this happens, the vapor becomes ionized. As a result, many ions are produced along the path of the particle (“CLOUD CHAMBERS”). These ions are visible to the naked eye in the cloud chamber and the bright, thick trails of the alpha particle are what were counted in the experiment. Other particle tracks that can be viewed in a cloud chamber are muons, beta particles, single protons, particle decays, and the occasional positron.

The alpha particle tracks that are visible in the cloud chamber are all assumed to come from radon222, an unstable isotope of uranium238. Radon only has a halflife of 3.8 days, thus decays rather quickly (“What are the Radon Progeny?”). There is a slight possibility due to this factor that some of the alpha particle tracks actually come from polonium218, but because Colorado, and Boulder county specifically, has very high radon levels, thus a house’s supply would be constantly refurbished. It can be assumed that the tracks come straight from radon rather than polonium.

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All the houses tested in this experiment have some sort of mitigation system in place which should block a larger amount of radon, so that the house’s radon levels are at a stable and normal amount. Figure 3 below is a diagram of the Radon Progeny chain in which the halflives of each element and type of radiation they emit is shown.

Figure 3

Figure 3 shows the Radon Progeny chain in which the decay process is shown as Radon222 decays into Lead206.The type of radiation each isotope gives out is also portrayed.

What are the Radon Progeny (formerly Radon Daughters)? (1998, June 3). Retrieved March 27, 2016, from

http://www.ccnr.org/radon_chart.html

.

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3. Results and Data Analysis

Each number of alpha particles was divided by the time in which they were counted to produce the number of alpha particles per second. For example, if 69 tracks were counted in a time of 30 seconds, then 69 was divided by 30, arriving at a total of 2.3 alpha particle tracks per second. Such tables can be found in Appendix B.

From these tables, averages were collected to narrow three samples for each floor per trial down to one samples for each floor per trial. These averages were condensed into one table per house. Floor 0 is the basement floor, floor one is the main floor, and floor 2 is the upper floor. Such tables can be seen in Tables 1–6. Trial One Trial Two Trial Three Trial Four Trial Five

Floor 0 2.1 2.3 2.1 2.1 2.1

Floor 1 1.7 1.8 1.8 1.8 1.9

Floor 2 1.7 1.7 1.7 1.8 1.8

Table 1 Table 1 describes the average amount of alpha particle tracks per second for each floor.

The data is that of House #1. House #1’s underlying rock type is colluvium. Trial One Trial Two Trial Three Trial Four Trial Five

Floor 0 2.8 2.8 2.7 2.9 2.7

Floor 1 2.1 1.7 1.9 1.9 2.0

Floor 2 1.8 1.9 1.8 1.8 1.8


The data is that of House #2. House #2’s underlying rock type is colluvium.

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Trial One Trial Two Trial Three Trial Four Trial Five

Floor 0 1.1 1.3 1.5 1.3 1.4

Floor 1 1.3 1.0 1.1 1.3 1.2

Floor 2 1.0 0.9 1.1 1.2 1.1

Table 3

Table 3 describes the average amount of alpha particle tracks per second for each floor. The data is that of House #3. House #3’s underlying rock type is colluvium.


Floor 0 1.1 1.1 1.1 1.3 1.1

Floor 1 0.9 0.8 0.7 0.8 0.7

Floor 2 0.5 0.7 0.6 0.6 0.4


The data is that of House #4. House #4’s underlying rock type is shale.


Floor 0 2.4 2.2 2.3 2.3 2.4

Floor 1 2.0 2.0 1.9 1.9 2.0

Floor 2 1.3 1.3 1.3 1.4 1.4

Table 5

Table 5 describes the average amount of alpha particle tracks per second for each floor. The data is that of House #5. House #5’s underlying rock type is shale.


Floor 0 1.3 1.2 1.4 1.3 1.2

Floor 1 1.1 1.2 1.2 1.2 1.1

Floor 2 0.9 0.9 1.0 1.0 0.9

Table 6

Table 6 describes the average amount of alpha particle tracks per second for each floor. The data is that of House #6. House #6’s underlying rock type is shale.

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A graph was made for each of the above data tables so the data can be easily compared side to side. Figure 4 below is an example of one of said graphs. The remainder of the graphs can be found in Appendix C.

Figure 4

Figure 4 is a bar graph of the data collected from House #1. Floor 0, the basement floor, is

represented by the blue color; floor 1, the main floor, is represented by the color red; and floor 2, the upper floor, is represented by the color green. The graph depicts the averages of the raw data, as explained above, not the raw data itself.

The averages for each trial were averaged again to get one average amount of alpha

particles per second for each floor, so that there is one average per floor and three per house. This can be viewed in Table 7 below.

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House #1 House #2 House #3 House #4 House #5 Hosue #6

Floor 0 2.1 2.8 1.3 1.1 2.3 1.3

Floor 1 1.8 1.9 1.2 0.8 1.9 1.2

Floor 2 1.7 1.8 1.1 0.6 1.3 1.0 Table 7

Table 7 represents the averages per floor for all six houses that were tested. These were the

best results for comparison purposes. A graph of this table can be seen in Figure 5 below.

Figure 5

Figure 5 shows the averages of each floor of each house compared to each other. The

xaxis is the house number. The blue represents the basement floor, the red the middle floor, and the green the upper floor.

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4. Discussion of Results

The data in Figure 5 shows the averages for each floor of all the houses compared to each other. The blue bar exceeds the other two in all six cases. This means that there was, in fact, consistently more alpha particles (hence more radon) on the basement level than the upper floors of the houses. The margins between the basement floor and the upper floor ranged from 0.2 to 1.0 alpha particles per second. Whether there was altogether more alpha particles on the houses over shale or colluvium was overall inconclusive. The number of alpha particles on the basement of the floor and the main floor was much more closely related, with a margin ranging from 0.1 to 0.2 alpha particles per second.

The house that produced the greatest amount of alpha particles, as shown in Table 1and Figure 5 is House #2. This could mean that the mitigation system in this house is old, weak, or that this house is built in a way that amasses a greater amount of radon. House #1 is a close second for the greatest amount of alpha particle tracks observed. Both of these houses lie on top of colluvium.

The house that produced the least amount of alpha particles was House #4, as shown in Table 4 and Figure 5. The highest amount of alpha particles for this house was less than that of the lowest for House #2. This could mean that House #4 has a very well developed mitigation system or that the house is built in a way that is different than the build of House #2. The difference could also be size related. House #2 was significantly bigger than House #4, thus there was less room for the gas to collect in. The house with the next least amount of alpha particles was House #6, followed closely by House #3, as shown in Figure 5 and Tables 3 and 6.

Despite the vast differences between the amount of alpha particles between each house, there is consistently more alpha particles from radon on the lowest floor of the house than the highest, thus proving the hypothesis to be correct. The data shows that the basement floor is the correct place to place a mitigation system, as a greater amount of gas assembles there than on the other two floors. Placing the mitigation system in the basement will ensure that radon gas is being filtered out of the house in the most efficient and safest way.

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Error Analysis: Floor 0 Floor 1 Floor 2

Mean 1.8 1.5 1.3

Median 1.7 1.5 1.2

Minimum 1.1 0.8 0.6

Maximum 2.8 1.9 1.8

Mode 1.3 1.9 NA

Range 1.7 1.1 1.2

Standard Deviation 0.7 0.5 0.5

Figure 6

Floor 0 – Floor 1 Floor 1 – Floor 2 Floor 2 – Floor 0

TTest 0.017 0.021 0.005

Figure 7

Figure 6 and Figure 7 show the statistical analyses that were taken from the results. The averages, taken from all the previous averages, of the amount of alpha particle per each floor per trial were taken and condensed into three final averages – one for each floor. The median for Floor 0 is greater than that of the other two. The same goes for every other statistic until the mode, in which the statistic from Floor 1 is greater than that of Floor 0. TTests and standard deviation were also taken as methods of comparison and error analysis.

There was a moderate amount of error in this experiment. A standard deviation test was taken for each set of data in Table 7. The closer the standard deviation is to one, the more closely related the data in each set is to each other. In this case, the numbers aren’t terribly far from one considering, with the closest being that of Floor 0.

A ttest was also taken between each pair of floors. This resulted in very low numbers, which is a good thing in this case. In ttests, the number 0.05 is the watershed – as in any number that is less than 0.05 shows a significant difference between the data sets. The ttests are all less than 0.05, showing significant difference. In the ttest between Floor 0 and Floor 1, there is a 98.3% chance that the data sets are different. In the ttest between Floor 1 and Floor 2, there is a 97.9% chance that the data sets are different. Lastly, in the ttest between Floor 2 and Floor 0, there is a 99.5% chance that the data sets are different. The two sets that had the most significant difference were Floor 0 and Floor 2, proving the hypothesis correct.

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Comparison of Results:

Many other forms of particle detectors have been made to detect radiation, such as the bubble chamber, photographic plates, the ionization chamber, etc. Charles Rees Wilson, inventor of the Wilson cloud chamber, began working on the cloud chamber in the early 20th century. He was the first person to photograph the tracks of individual alpha and beta particles. Many important discoveries have resulted from work on the cloud chamber, such as Compton recoil electrons (the Compton Effect), the discovery of positrons, the transmutation of atomic nuclei, etc (“C.T.R. Wilson –– Biographical”). Other studies have also been done surrounding the central idea of radiation in a cloud chamber, in which it has been concluded that a cloud chamber could be used as a sort of radon detector. Next Steps:

The next step in this experiment would first and foremost be to eliminate all possible error, in the sense that all trials would be exactly the same, so that there is a smaller chance of inconsistency. It would also be interesting to carry the experiment a step further by applying a strong magnet to one side of the chamber and testing how and if the tracks bend. Grid lines could be placed on the bottom of the chamber to test this. Some sort of system could also be set up in which the amount of radiation that can travel through certain materials of certain widths could be tested. Different brands or types of isopropyl alcohol could also be tested to determine the performance level in a cloud chamber.

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Sophie Reeves

Colorado Science and Engineering Fair April 79, 2016

Technical Writing Paper 5. Conclusion

Based on this experiment, it can be concluded that the level of a house affects the resulting radon count, thus providing supporting data that the basement floor is the most effective place to put a mitigation system. Radon222 is a gas that comes from the ground when uranium238 in the soil decays. It is a natural part of the environment and tends to accumulate in high quantities in houses or other closedin areas because it is harder for the gas to disperse. Radon has a halflife of only 3.8 days, so it decays relatively rapidly into polonium218. During the decay process, the radon emits alpha particles, a type of subatomic particle made up of two protons and two neutrons. Alpha particles themselves are too fast and small to be viewed directly, but their tracks can be viewed indirectly in a type of particle detector known as a cloud chamber. Uranium comes from the ground, hence there should be a lesser quantity of it the higher in the atmosphere that a detector is tested. For these reasons, if a cloud chamber is tested in the basement, on the main floor, and on the upper floor of a house, then there should be a greater quantity of alpha particles produced by radon in the basement than on the upper floors.

A cloud chamber was built in this experiment to test the amount of tracks produced by radon and cosmic rays per floor of a house. Six houses were tested in total. The hypothesis was proven to be correct – there was more alpha particles produced from radon222 on the basement floor of a house than the upper floors, hence clarifying the right spot to place a mitigation system for homeowners. The data was averaged down to the best possible method of comparison, and the comparison is clearly demonstrated in Figure 5. Standard deviation tests proved that the data in each set was similar to itself, and that there was a moderate amount of error in this experiment. All the ttests showed great percentages of chance of significant difference between each data set, the largest being a 99.5% chance of difference between the data of Floor 0 and the data of Floor 2.

This project was conducted mainly for the purpose of its engagement with radioactivity and radon222 in particular. Radon is created naturally, yet it can be very harmful in high quantities. Most houses have mitigation systems in place which should filter out a large portion of the radiation. Despite this, however; many homeowners who did not build the house they live in do not know how old and/or powerful their mitigation system is. A cloud chamber, such as the one created in this experiment can act as a radon detector of a sort and ensure that the homes that people live in are safe and have a stable amount of natural radiation. This experiment was also conducted to make sure that the basement floor of a house is the most rational and efficient place to place the mitigation system, as it has the most radon radiation.

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Sophie Reeves


Technical Writing Paper Acknowledgements

I would like to thank both of my parents as well as my nanny, Kelsey, for continuously getting me dry ice and other supplies I’ve needed throughout the course of this experiment. Thank you to Mrs. Keeney for being my science fair mentor and providing me with lots of support and help and to Mr. Teasdale and Mr. Perkins for also supporting me through the process. I would also like to thank Dr. Eric Cornell and his team of graduate students for assisting me in my pretesting and allowing me to observe them using their chunk of thorium in my cloud chamber in their lab. Finally, I would like to thank all of the people that volunteered their houses to be part of my experiment. You were all an incredible help, and my experiment wouldn’t of survived without your generosity.

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Sophie Reeves


Technical Writing Paper Works Cited

CLOUD CHAMBERS. (2008, June 30). Retrieved January 16, 2016, from

http://njsas.org/projects/atoms/cloud_chamber/index.php

Colluvium. (n.d.). Retrieved January 16, 2016 from http://www.merriamwebster.com/dictionary/colluvium

C.T.R. Wilson Biographical. (2014). Retrieved August 21, 2015, from

http://www.nobelprize.org/nobel_prizes/physics/laureates/1927/wilsonbio.html

Find Information about Local Radon Zones and Radon Programs. (n.d.). Retrieved March 27, 2016, from

https://www.epa.gov/radon/findinformationaboutlocalradonzonesandradonprograms#radonmap

Galen, M. (1987, February 14). Nowhere to Run from Radon. The Nation. 180182.

Home Buyer's and Seller's Guide to Radon. (n.d.). Retrieved March 27, 2016, from https://www.epa.gov/radon/homebuyersandsellersguideradon

Health effects of exposure to radon. (1998). Washington, D.C.: National Academy Press. Radon in Colorado. (n.d.). Retrieved September 13, 2015, from

http://www.coepht.dphe.state.co.us/environment/radon.aspx

Radon. (n.d.). Retrieved June 1, 2015 from http://www.epa.gov/radon/states/colorado.html

Shale. (n.d.) Retrieved January 16, 2016 from http://www.merriamwebster.com/dictionary/shale There is no Safe Radon Level! (n.d.). Retrieved March 27, 2016, from http://www.radonseal.com/radonlevel.htm Venton, D. (2015, May 27). Uncover the Universe's Mysteries From the Comfort of Home. Retrieved March 27, 2016, from

http://www.wired.com/2015/05/tabletopphysics/ 18

What are cosmic rays? (n.d.). Retrieved March 27, 2016, from http://www.cosmicray.com/

What are the Radon Progeny (formerly Radon Daughters)? (1998, June 3). Retrieved March 27, 2016, from

http://www.ccnr.org/radon_chart.html

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Sophie Reeves


Technical Writing Paper Appendix A

All Raw Data.

Data is measured as number of alpha particles per given time period.

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House #1

Trial #1

30 s 60 s 90 s

Floor 0 69 125 184

Floor 1 52 99 155

Floor 2 57 92 149

Trial #2

30 s 60 s 90 s

Floor 0 67 133 220

Floor 1 54 121 152

Floor 2 53 95 150

Trial #3

30 s 60 s 90 s

Floor 0 71 120 180

Floor 1 60 114 147

Floor 2 46 101 161

Trial #4

30 s 60 s 90 s

Floor 0 68 118 179

Floor 1 65 102 148

Floor 2 56 100 162

Trial #5

30 s 60 s 90 s

Floor 0 63 102 216

Floor 1 70 100 149

Floor 2 64 96 157

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House #2

Trial #1

30 s 60 s 90 s

Floor 0 101 145 228

Floor 1 68 118 173

Floor 2 54 106 158

Trial #2

30 s 60 s 90 s

Floor 0 103 148 221

Floor 1 59 108 130

Floor 2 62 102 167

Trial #3

30 s 60 s 90 s

Floor 0 82 157 246

Floor 1 62 106 175

Floor 2 55 101 165

Trial #4

30 s 60 s 90 s

Floor 0 97 138 284

Floor 1 58 127 140

Floor 2 54 113 161

Trial #5

30 s 60 s 90 s

Floor 0 94 149 233

Floor 1 66 116 164

Floor 2 57 109 160

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House #3

Trial #1

30 s 60 s 90 s

Floor 0 32 74 100

Floor 1 51 62 94

Floor 2 33 59 86

Trial #2

30 s 60 s 90 s

Floor 0 41 80 120

Floor 1 27 62 108

Floor 2 31 55 78

Trial #3

30 s 60 s 90 s

Floor 0 54 82 113

Floor 1 48 59 72

Floor 2 28 48 130

Trial #4

30 s 60 s 90 s

Floor 0 45 73 98

Floor 1 44 70 115

Floor 2 41 69 88

Trial #5

30 s 60 s 90 s

Floor 0 48 75 114

Floor 1 46 64 99

Floor 2 37 63 94

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House #4

Trial #1

30 s 60 s 90 s

Floor 0 37 56 98

Floor 1 26 52 96

Floor 2 14 44 40

Trial #2

30 s 60 s 90 s

Floor 0 38 66 97

Floor 1 30 39 57

Floor 2 23 48 55

Trial #3

30 s 60 s 90 s

Floor 0 33 60 101

Floor 1 19 45 61

Floor 2 17 31 51

Trial #4

30 s 60 s 90 s

Floor 0 45 64 113

Floor 1 27 43 66

Floor 2 18 33 50

Trial #5

30 s 60 s 90 s

Floor 0 28 76 102

Floor 1 17 41 70

Floor 2 9 28 45

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House #5

Trial #1

30 s 60 s 90 s

Floor 0 81 133 198

Floor 1 61 116 191

Floor 2 37 89 112

Trial #2

30 s 60 s 90 s

Floor 0 69 129 189

Floor 1 63 113 174

Floor 2 48 75 100

Trial #3

30 s 60 s 90 s

Floor 0 82 123 194

Floor 1 55 110 170

Floor 2 42 72 126

Trial #4

30 s 60 s 90 s

Floor 0 78 120 197

Floor 1 56 107 186

Floor 2 40 88 119

Trial #5

30 s 60 s 90 s

Floor 0 84 128 204

Floor 1 62 113 178

Floor 2 45 74 131

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House #6

Trial #1

30 s 60 s 90 s

Floor 0 33 85 116

Floor 1 28 69 103

Floor 2 24 66 75

Trial #2

30 s 60 s 90 s

Floor 0 36 84 90

Floor 1 42 71 96

Floor 2 29 53 82

Trial #3

30 s 60 s 90 s

Floor 0 41 92 115

Floor 1 34 76 102

Floor 2 30 62 93

Trial #4

30 s 60 s 90 s

Floor 0 42 86 97

Floor 1 37 81 98

Floor 2 27 65 88

Trial #5

30 s 60 s 90 s

Floor 0 32 89 106

Floor 1 30 76 99

Floor 2 22 69 84

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Appendix B

Each number of alpha particles was divided by the time in which they were counted to produce the number

of alpha particles per second. The unlabeled quantitative data are these values.

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House #1

Trial #1

Floor 0 2.3 2.1 2.0

Floor 1 1.7 1.7 1.7

Floor 2 1.9 1.5 1.7

Trial #2

Floor 0 2.2 2.2 2.4

Floor 1 1.8 2.0 1.7

Floor 2 1.8 1.6 1.7

Trial #3

Floor 0 2.4 2.0 2.0

Floor 1 2.0 1.9 1.6

Floor 2 1.5 1.7 1.8

Trial #4

Floor 0 2.3 2.0 2.0

Floor 1 2.2 1.7 1.6

Floor 2 1.9 1.7 1.8

Trial #5

Floor 0 2.1 1.7 2.4

Floor 1 2.3 1.7 1.7

Floor 2 2.1 1.6 1.7

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House #2

Trial #1

Floor 0 3.4 2.4 2.5

Floor 1 2.3 2.0 1.9

Floor 2 1.8 1.8 1.8

Trial #2

Floor 0 3.4 2.5 2.5

Floor 1 2.0 1.8 1.4

Floor 2 2.1 1.7 1.9

Trial #3

Floor 0 2.7 2.6 2.7

Floor 1 2.1 1.8 1.9

Floor 2 1.8 1.7 1.8

Trial #4

Floor 0 3.2 2.3 3.2

Floor 1 1.9 2.1 1.6

Floor 2 1.8 1.9 1.8

Trial #5

Floor 0 3.1 2.5 2.6

Floor 1 2.2 1.9 1.8

Floor 2 1.9 1.8 1.8

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House #3

Trial #1

Floor 0 1.1 1.2 1.1

Floor 1 1.7 1.0 1.0

Floor 2 1.1 1.0 1.0

Trial #2

Floor 0 1.4 1.3 1.3

Floor 1 0.9 1.0 1.2

Floor 2 1.0 0.9 0.9

Trial #3

Floor 0 1.8 1.4 1.3

Floor 1 1.6 1.0 0.8

Floor 2 0.9 0.8 1.4

Trial #4

Floor 0 1.5 1.2 1.1

Floor 1 1.5 1.2 1.3

Floor 2 1.4 1.2 1.0

Trial #5

Floor 0 1.6 1.3 1.3

Floor 1 1.5 1.1 1.1

Floor 2 1.2 1.1 1.0

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House #4

Trial #1

Floor 0 1.2 0.9 1.1

Floor 1 0.9 0.9 1.1

Floor 2 0.5 0.7 0.4

Trial #2

Floor 0 1.3 1.1 1.1

Floor 1 1.0 0.7 0.6

Floor 2 0.8 0.8 0.6

Trial #3

Floor 0 1.1 1.0 1.1

Floor 1 0.6 0.8 0.7

Floor 2 0.6 0.5 0.6

Trial #4

Floor 0 1.5 1.1 1.3

Floor 1 0.9 0.7 0.7

Floor 2 0.6 0.6 0.6

Trial #5

Floor 0 0.9 1.3 1.1

Floor 1 0.6 0.7 0.8

Floor 2 0.3 0.5 0.5

31

House #5

Trial #1

Floor 0 2.7 2.2 2.2

Floor 1 2.0 1.9 2.1

Floor 2 1.2 1.5 1.2

Trial #2

Floor 0 2.3 2.2 2.1

Floor 1 2.1 1.9 1.9

Floor 2 1.6 1.3 1.1

Trial #3

Floor 0 2.7 2.1 2.2

Floor 1 1.8 1.8 1.9

Floor 2 1.4 1.2 1.4

Trial #4

Floor 0 2.6 2.0 2.2

Floor 1 1.9 1.8 2.1

Floor 2 1.3 1.5 1.3

Trial #5

Floor 0 2.8 2.1 2.3

Floor 1 2.1 1.9 2.0

Floor 2 1.5 1.2 1.5

32

House #6

Trial #1

Floor 0 1.1 1.4 1.3

Floor 1 0.9 1.2 1.1

Floor 2 0.8 1.1 0.8

Trial #2

Floor 0 1.2 1.4 1.0

Floor 1 1.4 1.2 1.1

Floor 2 1.0 0.9 0.9

Trial #3

Floor 0 1.4 1.5 1.3

Floor 1 1.1 1.3 1.1

Floor 2 1.0 1.0 1.0

Trial #4

Floor 0 1.4 1.4 1.1

Floor 1 1.2 1.4 1.1

Floor 2 0.9 1.1 1.0

Trial #5

Floor 0 1.1 1.5 1.2

Floor 1 1.0 1.3 1.1

Floor 2 0.7 1.2 0.9

33



Appendix C

34

the relationship between cloud chambers, alpha particles

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