The whole point of knowledge is to produce both m Essays

"The whole point of knowledge is to produce both meaning and purpose in our personal lives" I relate to this quote on a personal level because this is how I think and feel about things like religions and pretty much everything, it's just to produce meaning in a meaningless life nothing truly matters, honestly without knowledge we would be just mindless beings walking around the earth with no purpose what so ever but the thing about knowledge is you can never know everything and our minds are forever expanding with knowledge and we are always learning new things everyday but no one truly knows why we do we just do and that produce both meaning and purpose to our everyday lives and that's what I think this quote is talking about. Our personal lives will have a greater purpose if we are able to reflect and learn about a certain subject. The main areas of knowledge that have greater influence towards the path taken in life are ethics, intuition, and religious knowledge. One KQ I have would be "how do we know whether we need to gain knowledge to give meaning and purpose to our lives?" Ethics are the basic concepts and principles of a sane human being. The study of universal values such as the equality of all, obedience towards law health, and increasingly, the protection of the natural environment. However, these values depend a lot on the cultural identity someone was brought on, their preferences and their own values. In other words, ethics is a gathering of personal rules that each person applies to its own values and morals in order to make decisions. It is coherent to state that the ethics may have a great impact on a person's life path as it may reveal questions in life, an example would be you someone but they are already in a devoted relationship with someone, so you decide not to attempt any romantic relationship with them because: you don't want to disturb their relationship and cause their relationship emotional harm; the world is full of single, intelligent and beautiful people. There can be many examples and sometimes a small action or omission can have significant consequences. Some actions can start positive chain reactions and can lead to positive net results. Being mindful, being self-confident and letting your "heart flow" is a good way to be more ethical in your daily life. History, The word 'history' is derived from the Greek noun 'historia' meaning 'inquiry or research, historical knowledge is often used to define meaning and purpose in personal lives' . Real life examples could be drawn from nationalism, state ideology, religious or economic systems. Early man didn't know how to light fire but with time, they gained knowledge and started to evolve with the motive to know more and today there are no early man but there are us, History provides a terrain for moral contemplation. Studying the stories of individuals and situations in the past allows a student of history to test his or her own moral sense, History also helps provide identity, and this is unquestionably one of the reasons all modern nations encourage its teaching in some form. Historical data include evidence about how families, groups, institutions and whole countries were formed and about how they have evolved while retaining cohesion. The importance of history is in its capacity to h elp one to draw conclusions from the past events. It may be said that history is to the human race, what memory is to each man. It sheds the light of the past upon the present, thus helping one to understand oneself, by making one acquainted with other peoples. History makes one's life richer by giving meaning to the books one reads, the cities one visits or the music one hears. Memory is mainly defined as the faculty by which the mind stores and remembers information and something remembered from the past (Van de Lagemaat, 2015:252). Our memory shapes our personal and shared identity. A large amount of second hand knowledge has been passed on through language to become part of the shared knowledge of knowledge communities. This knowledge is at its turn stored and passed

Avatar 1 Essay

Avatar 1 Essay Avatar 1 Essay Title: Avatar Director: James Cameron Text Type: Film Response Number: 2 In the film â€Å"Avatar† by James Cameron, the story unfolds in the future in another planet named Pandora. Here human soldiers and scientists are involved in a mission to obtain supplies of an immensely valuable mineral called Unobtainium, but their progress is affected by local â€Å"savages† known as the Na’vi tribe. These so called â€Å"savages† appear three meters tall with striped cyan coloured skin. They are a race which bears a close representation to human qualities. Former crippled marine Jake Sully is a part of the project to access the Unobtanium but changes allegiances as he discovers the Na’vi people are not â€Å"savages† and realises the lengths his own race is taking to own the substance, as the humans are destroying the Na’vi village for it. This enabled me to see that despite the Na’vi people of Pandora presenting not even a remote threat to the humans, they react by sending heavy armoury to attack the locals for the valuable Unobtainium, illustrating their greed and selfishness. Cameron also portrays important messages conveyed with a minimum of telling and a maximum of showing  ­ such as the spiritual sign from Eywa, which is a strong belief for the Na’vi tribe. This shows us how important religion is for The Na’vi. It astounded me that an established race such as the humans, still want to destroy another entire race just to grow their civilization more. Despite the Na’vi not being as advanced as the humans they still want to take away what little they have, to gain even more power and wealth. This allows me to see the effects that money has on the majority of people  ­ becoming selfish and greedy. â€Å"Avatar† showed me the lengths to which people will go, including crippling others just to have more money or power, which I could see go hand in hand. Greed to me personally is one of the most disgusting traits a person can have and unfortunately is rampant in the society we live in today. An example of this greed in todays society are loan sharksÍ ¾ who offer money to people at extremely high interest rate and more often than not to people who are not in a position to take on loans. Societies will always be at risk when power is abused highlighting the greed that hides beneath. I think the idea of what â€Å"you† personally believe in plays a major part in the film. Jake realises who the real enemy is in this conflict and begins a whole new embodied way of life  ­ â€Å"One life ends, another begins†. Jake Sully develops through the film, from a marine â€Å"knock off† to the leader of the Na’vi after facilitating communication, showing a tremendous amount of courage throughout the film. I think staying true to yourself is important because letting other people's decisions influence your own can leave you vulnerable to manipulation. It also leaves you susceptible to being someone else’s slave, where all your actions are not yours, but instead theirs but completed by you. Staying true to yourself is important everyday in modern societyÍ ¾ making decisions you personally support deep down so you can live your life to its fullest. During the film I realised that everything seems connected on the planet Pandora on a

Black History - Index of Inventors and Patent Holders

Black History - Index of Inventors and Patent Holders Black history inventors are listed alphabetically: use the A to Z index bar to navigate and select or just browse the many listings. Each listing has the name of the black inventor followed by the patent number(s) which is the unique number assigned to an invention when a patent is issued, the date the patent was issued, and a description of the invention as written by the inventor. If available, links are provided to in-depth articles, biographies, illustrations and photos on each individual inventor or patent. How to submit to the database. R Sammons to Scottron, Shaw to Smith, Smoot to Sweeting T Walter H Sammons #1,362,823, 12/21/1920, Comb Adolphus Samms #3,000,179, 9/19/1961, Rocket engine pump feed system#3,199,455, 8/10/1965, Multiple stage rocket#3,257,089, 6/21/1966, Emergency release for extraction chute#3,310,938, 3/28/1967, Rocket motor fuel feed George T Sampson #312,388, 2/17/1885, Sled propeller#476,416, 6/7/1892, Clothes drier Henry Thomas Sampson #3,140,210, 7/7/1964, Binder system for propellants and explosives#3,212,256, 10/19/1965, Case bonding system for cast composite propellants#3,591,860, 7/6/1971, Gamma-Electrical Cell, (co-inventor George H Miley, this patent is not for cell phone tecnology) Dewey S C Sanderson #3,522,011, 7/28/1970, Urinalysis machine Ralph W Sanderson #3,362,742, 1/9/1968, Hydraulic shock absorber Richard L Saxton #4,392,028, 7/5/1983, Pay telephone with sanitized tissue dispenser Virginia Scharschmidt #1,708,594, 4/9/1929, Safety window cleaning device Henry Scott #4,881,528, 11/21/1989, Spinal traction and support unit used while seated Howard L Scott #3,568,685, 3/9/1971, Treating human, animal and synthetic hair with a waterproofing composition J C Scott #D 212,334, 10/1/1968, Shadow box Linzy Scott #4,275,716, 6/30/1981, Knee brace Robert P Scott #524,223, 8/7/1894, Corn silker Samuel R Scottron #224,732, 2/17/1880, Adjustable window cornice#270,851, 1/16/1883, Cornice#349,525, 9/21/1886, Pole tip#481,720, 8/30/1892, Curtain rod#505,008, 9/12/1893, Supporting bracket R Sammons to Scottron, Shaw to Smith, Smoot to Sweeting T Â   Earl D Shaw #4,529,942, 7/16/1985, Free-electron amplifier device with electromagnetic radiation delay element Glenn Shaw #5,046,776, 9/10/1991, Fascia protector for fuel tank filler Jerry Shelby #5,328,132, 7/12/1994, Engine protection system for recoverable rocket booster Dennis W Shorter #363,089, 5/17/1887, Feed rack Wanda A Sigur #5,084,219, 1/28/1992, Method of fabricating composite structures Esteban Silvera #3,718,157, 5/27/1973, Ram-valve level indicator Joycelyn Simpson look under Joycelyn Harrison Stephen Chambers Skanks #587,165, 7/27/1897, Sleeping car berth register Isadore Small #3,814,948, 6/4/1974, Universal on-delay timer Brinay Smartt #799,498, 9/12/1905, Reversing-valve#935,169, 9/28/1909, Valve gear#1,052,290, 2/4/1913, Wheel Bernard Smith #4,544,535, 10/1/1985, Method or preparing nonlaminating anisotropic boron nitride John Winsor Smith #647,887, 4/17/1900, Game Jonathan S Smith #3,432,314, 3/11/1969, Transparent zirconia composition and process for making same Joseph H Smith #581,785, 5/4/1897, Lawn sprinkler#601,065, 3/22/1898, Lawn sprinkler Mildred E Smith #4,230,321, 10/28/1980, Family relationships card game Morris L Smith #3,389,108, 6/18/1968, Printing fluid comprising an aqueous solution of a water-soluble dye and a thermosetting vinylsulfonium polymer#4,882,221, 11/21/1989, Chemically treated paper products - towel and tissue#4,883,475, 11/28/1989, Chemically treated paper products - towel and tissue Peter D Smith #445,206, 1/27/1891, Potato digger#469,279, 2/23/1892, Grain binder Robert T Smith #1,970,984, 8/21/1934, Spraying machine Samuel C Smith #3,956,925, 5/18/1976, Hardness tester R Sammons to Scottron, Shaw to Smith, Smoot to Sweeting T Â   Lanny S Smoot #4,565,974, 1/21/1986, Optical receiver circuit with active equalizer#4,890,314, 12/26/1989, Teleconferencing facility with high resolution video display#4,928,301, 5/22/1990, Teleconferencing terminal with camera behind display screen William Snow #437,728, 10/7/1890, Liniment Harde Spears #110,599, 12/27/1870, Improvement in portable shields for infantry and artillery Richard Bowie Spikes #972,277, 10/11/1910, Self-locking rack for billiard cues#1,590,557, 6/29/1926, Combination milk bottle opener and cover#1,828,753, 10/27/1932, Method and apparatus for obtaining average samples and temperature of tank liquids#1,889,814, 12/6/1932, Automatic gear shift#1,936,996, 11/28/1933, Transmission and shifting means therefor#3,015,522, 1/2/1962, Automatic safety brake system Osbourne C Stafford #3,522,558, 8/4/1970, Microwave phase shift device Elbert Stallworth #1,687,521, 10/16/1928, Electric heater#1,727,842, 9/10/1929, Electric chamber#1,972,634, 9/4/1934, Alarm clock electric switch Arnold F Stancell #3,657,113, 4/18/1972, Separating fluids with selective membranes George B. D. Stephens #2,762,377, 9/11/1956, Cigarette holder and ash tray John Standard #413,689, 10/29/1889, Oil stove#455,891, 7/14/1891, Refrigerator Albert Clifton Stewart #3,255,044, 6/7/1966, Redox couple radiation cell#3,255,045, 6/7/1966, Electric cell Earl M Stewart #2,031,510, 2/18/1936, Arch and heel support (co-inventor Seymour Shagrin) Enos W Stewart #362,190, 11/27/1887, Punching machine#373,698, 5/3/1887, Machine for forming vehicle seat bars Marvin Charles Stewart #3,395,271, 7/30/1968, Arithmetic unit for digital computers#3,605,063, 9/14/1971, System for interconnecting electrical components Thomas Stewart #375,512, 12/27/1887, Metal bending machine#499,402, 6/13/1893, Mop#499,895, 6/20/1893, Station indicator Henry F Stilwell #1,911,248, 5/30/1933, Means for receiving mail and other matter on aeroplanes while in motion Rufus Stokes #3,378,241, 4/16/1968, Exhaust purifier#3,520,113, 7/14/1970, Air pollution control device Edward H Sutton #149,543, 4/7/1874, Improvement in cotton cultivators James A Sweeting #594,501, 11/30/1897, Device for rolling cigarettes#605,209, 6/7/1898, Combined knife and scoop Continue black history database T

Selected Family Health Promotion Assessment and Initiative Essay - 1

Selected Family Health Promotion Assessment and Initiative - Essay Example In most first world countries, health visitors offer spontaneous public health service in accordance to the actions taken by the government to promote health and provide preventive care among families and communities. These health visitors maintain a number of cases to be dealt with, particularly families within a certain area with children of 5 years old and below, to supply health services through specialized home visiting that focuses on individual health care needs, clinic contacts, as well as health-related activities at a community level. Since the early 1990s, the British National Health Service has aimed to implement policies that will address health inequalities (Greater London Authority 2002), reduce all health-related gaps, and improve the living standards of those experiencing the worst health conditions in the society (Department of Health 2001). Initially, the pressure in decreasing the amount of time allocated for home visiting was consequently followed by the increase d emphasis on disadvantaged families. Owing to such priorities, major decisions were made with regards to the assessment of health needs when families are first visited by health visitors to identify the appropriate frequency of possible contacts in the future. There is not a single approach that is accepted as the sole tool for assessing health needs; there is also no established agreements regarding the applicability of various approaches with which decisions about the frequency, level, and types of services to be provided are to be made. Elkan, Robinson, Williams, and Blair (2001) asserted that the main decision lies on the judgment of health professionals in ascertaining the frequency of communication and contact with families. There have been an increased number of studies that examine the processes integrated within health visitor needs assessment, especially in settling on the necessary contact frequency between the family and health visitor (Appleton 2002); however, there ar e fewer studies that highlight the structure the implementation of structured health needs assessment approaches. Nonetheless, majority of health institutions responsible for health visitors have implemented a type of structured guidance that can help make appropriate decisions about service provision in health visiting. The current study, then, focuses on the Developmental Model of Health and Nursing (DMHN) which emphasizes the development of healthy attitudes and behaviors that take place in the family. The DMHN generally pays attention to how family members create the strategies necessary for them to live a healthy life, focusing on the role of the entire family in developing the responses to health-related situations which can generally affect the family at an individual and group level (Ford-Gilboe 2002).Due to the model’s strengths-based direction, the DMHN can be very much applicable for evaluating and gaining insight especially about vulnerable groups of people. The f ollowing sections will then examine the application of the Developmental Model of Health and Nursing (DMHN) initially proposed by Alen (1977) to restructure health care systems and make them

What are the main benefits and costs of monetary union What are the Essay

What are the main benefits and costs of monetary union What are the main criteria for the optimality of a currency area - Essay Example Thus it eliminates a big hurdle in the way of trade. At the same time, countries get free from any exchange rate uncertainty; get smaller rates of transactions and more secure price transparency. A neutral body acts as central bank on behalf of all member nations of the monetary union. This body being neutral and free from influence of any nation makes it credible for not only all members of the monetary union, but also for outside world. For example, European Central Bank acts as a combined central bank of the European Union. Monetary union is the way of promoting greater economic alliance which is beneficial for all member states and the outside world. For example, it is easy today to deal with a group of 28 countries of Europe at a single platform named European Union. Optimal currency area is also known as optimal currency region. This area refers to single market areas having a single currency across the region. There are many elements that define the optimality of a currency area (Alexandre Swoboda, 1999). It is important to have these elements to become the member of an optimal currency area. So following is the main criteria for the optimality of a currency area: (University of North Carolina,

Huck Finn Vs. 19th Cevtury Ethnics Essay -- essays research papers

Ninetieth Century Morals vs. Huck’s Conscience   Ã‚  Ã‚  Ã‚  Ã‚  Sometimes making a stand for what is right, especially when it is totally against the customary beliefs of society, can never be an easy accomplishment.   Ã‚  Ã‚  Ã‚  Ã‚  In the novel, The Adventures Huckleberry Finn by, Mark Twain, the main character Huck, encounters many situations involving a question of morality. Considering the traditional protocol of his society, Huck must choose between his conscience or public ethics. In many cases Huck goes with his conscience, which always proves to be proper selection. Ironically, what Huck believes in, unapproved of in the ninetieth century, is the basis of accepted beliefs in our modern world. Huck lives with the guilt that all his choices could be considered immoral based on his society; yet, really his beliefs could be just in comparison to man’s conscience. Three of the major instances in the novel when Huck’s beliefs contrast those of the ninetieth century are when he questions the outcome of Jim, when he tries to comprehend the concept of the feud, and when he must decide whether to save the men on the Sir Walter Scott.   Ã‚  Ã‚  Ã‚  Ã‚  Although Huck’s choices concerning Jim’s life can be thought to be the moral and proper choices, Huck is pounded by his society’s teachings the Black men are property. When Huck first escapes from Pap and sets up camp on Jackson Island, he finds Jim has also found refuge there from the widow and Mrs. Watson. Huck is stunned at first when Jim tells him he escaped, because Huck knows that Mrs. Watson owns Jim, which makes him her rightful property. â€Å"People would call me a low-down Abolitionist and despise me for keeping mum,†(Twain 43) Huck knows that if he helped Jim that would make him an abolitionist, which could not be accepted role in the ninetieth century. Huck decides that he would help Jim escape, as he would never return to the town so it wouldn’t matter if he took Jim with him. After a long raft-ride, Huck and Jim are finally about to reach Cairo, which on their arrival would make Jim free. With the smell of freedom, Jim rambles on about how he would buy his wife and then steal his children. This sets off a spark in Huck, igniting his conscience and making him very uneasy. Huck couldn’t believe that Jim would steal property... ... of truth and intelligence, and one that should be entrusted in every person’s soul no matter if they are living in the Ninetieth century or today.   Ã‚  Ã‚  Ã‚  Ã‚  This combination of the three instances shows the dramatic difference between Huck’s conscience and the standard customs of the Ninetieth century. Huck showed great maturity and integrity in standing up for what he believed was the right choice. Although he believed his choices were immoral or unethical, we now know that it was quite the opposite, as the moral standards of this time were in essence the unethical choices and Huck’s were the proper choices. Huck could see the importance of friendship over possessions, and risked his life saving a run-away slave because of the uncomfortable emptiness he would experience had he turned in Jim. This portrayal of childhood knowledge can be examined in today’s society also. People grow to be prejudiced against certain types of people, just as Huck was as he was growing up. Luckily, Huck overcame this inborn prejudice by examining what really counts in life, and this is a lesson that everyone, from previous societies to today, needs to listen to.

Investigating the Inverse Square Law Essay

The inverse square law can also be applied to gravity, electric fields, light and sound. In relation to electric fields, the electric force in Coulomb’s law follows the inverse square law: ‘If gamma rays are a form of electromagnetic radiation and undergo negligible absorption in air, then the intensity, I, should vary inversely as the square of the distance between the source and the detector.’2 Air acts as an almost transparent medium to ?-rays, and the intensity (rate of energy arrival per unit area) of ?-rays emanating from a point source varies inversely as the square of the distance from the source.3 ?-rays fall into many distinct monoenergetic groups because of their variable energies which emanate from any particular emitter. The least energetic radiation will only pass through very thin foils, whereas the most energetic can penetrate up to several centimetres of lead.4 As ?-rays tend to produce 10-4 times as many ion-pairs per unit length as ?-particles do, measurements are usually carried out using a Geiger-Mller (G-M) tube.5 G-M tubes are widely used for detecting radiation and ionising particles. Source: http://en.wikipedia.org/wiki/Geiger-M%C3%BCller_tube The anode is a central thin wire which is insulated from the surrounding cathode cylinder, which is metal or graphite coated. The anode is kept at a positive potential and the cathode is earthed. The tube may also have a thin mica end window.6 When radiation enters the tube, a few electrons and ions are produced in the gas. If the voltage is above the breakdown potential (The minimum reverse voltage to make the diode conduct in reverse)7 of the gas, the number of electrons and ions are greatly multiplied. The electrons are attracted to the anode, and the positive ions move towards the cathode. The current flowing in the high resistance resistor (R) produces a pd which is amplified and passed to a counter which registers the passage of an ionising particle or radiation through the tube.8 The tube cannot be filled with air as the discharge persists for a short time after the radiation is registered. This is due to electrons being emitted from the cathode by the positive ions which arrive there. Instead, the tube is filled with argon mixed with a halogen vapour which quenches, reduces the intensity, the discharge quickly, ensuring that the registered radiation does not affect the recording of other ionising particles. When the G-M tube is detecting one particle, if another enters the tube it will not be detected. This is known as dead time; the average maximum being approximately 90 microseconds.9 Because this number is so small, it can justifiably be ignored for this experiment. Background radiation must be taken into account when taking readings from the source. Background radiation primarily comes from cosmic radiation and terrestrial sources.10 This radiation will affect the count and must be corrected. The level of this radiation varies with location and must be measured before conducting the experiment. Since I ? C: C ? 1 (d + d0)2 Therefore: d + d0 ? 1 Vc I ? 1 r2 Where: * d = distance * d0 = distance to be added to the measured distance, d, because of the reference point on the holder not coinciding with the source, and the effective counting space inside the GM tube may not be close to the window, then r = d + d0. * I = intensity * C = corrected count rate – the measured count rate minus the reading for background radiation11 Corrected count rate against 1/(d + d0)2 should produce a straight-line graph, passing through the origin, if the inverse square law is followed. Source: ‘A Laboratory Manual of Physics’ -F. Tyler, Page 269 The gradient of the line obtained is a measure of the strength of the source used in the experiment.12 The strength of the source is the activity, A=?N. The decay constant, ?, can be calculated using ? = ln2/t1/2 where the value for the half-life of Co-60 is 5.2714 years13. Therefore: ? = ln2/t1/2 = 0.693/1.664 x 108 = 4.175 x 10-9 The gradient of the straight line graph will equal ?N0e-?t so ? = gradient/ N0e-?t Safety Precautions: To ensure the utmost safety before, during and after this experiment, some guidelines should be followed: * Food and drink should not be consumed whilst in the same room as the source * Food items should not be stored in the same room as the source * The source should only be handled with long handled source handling tongs, and as little as possible * Hands should be washed thoroughly after contact with the source * If in contact with the source for an extended period, it is recommended that a monitoring badge is worn * As the source will radiate in only one direction, it should not be pointed at anyone * The source should be locked away in a lead lined box when not in use * Open wounds should be covered securely * Protective gloves should be warn when handling potentially contaminated items Errors: To reduce the possible errors within the experiment, an optical bench will be used to ensure that the G-M tube and the source are properly aligned throughout, as the source radiates in one direction, the alignment must remain standard. Also, for small distances, specifically the distance d0 which is the distance the source is from the opening of the holder plus the distance of detection from the window in the G-M tube, vernier callipers will be used to hold as much accuracy as possible. Vernier callipers read to fractions of a millimetre, making them much more accurate than other measuring devices. Other distances, such as distance d, can be measured with a metre rule as the distances are larger which decreases the possible error in measuring. There will also be the error of human reaction times from observing the final count and pressing the stopclock. To ensure accuracy, practise using the stop-clock and count switch until reasonably consistent results can be obtained. Preliminary Work: To decide on an appropriate voltage to use, the G-M tube and source set-up should be tested. Place the source approximately 10 cm from the window of the G-M tube and increase the voltage slowly, until the count rate stops changing dramatically. Plot a graph of the count-rate, C, against EHT voltage, V. Record the voltages V1 and V2 between which the rate of counting does not vary too much. If the rate of counting begins to rise after remaining much the same for a range of voltage do not raise the voltage any higher or the tube may suffer damage.14 The optimum operating voltage will be halfway between the voltage where the plateau begins and the voltage where it ends. To decide on the range of distances used, the source was moved close to the window of the G-M tube and was moved back slowly until the scaler could count adequately (5 cm). This is the smallest distance that will be used. To find the other extreme, the source was moved back until the count rate fell to a low value, but could still provide adequate results (35 cm). d (cm) N t1 (s) t2 (s) t3 (s) Ave. t 5.00 10,000 212 209 209 210.00 10.00 10,000 773 779 790 780.67 15.00 1000 180 220 205 201.67 20.00 1000 317 355 345 339.00 25.00 1000 457 469 437 454.33 30.00 1000 543 510 542 531.67 35.00 1000 749 720 735 734.67 From these preliminary results I have decided to time for 10,000 counts at 5 cm from the source, 5000 counts for 10cm from the source, and 1000 for 15 – 30cm. This is because any higher values will take considerably longer to measure. I will take three readings from each, as radioactive decay is a random process and it would be unlikely for more than three readings to be similar. An average will be calculated from the three values and the reading for the background radiation will be subtracted to find the corrected count rate. Equipment: * Geiger-Mller tube of , ? sensitive type * Decade scaler with variable EHT supply * Sealed cobalt-60 source – sealed to prevent contact with the source and to prevent isotropic radiation * Long handled source handling tongs – to prevent contact with the source * Optical bench with source holder – to ensure constant alignment * Stop-clock, readable to at least two decimal places * Vernier callipers – to measure the distance d0 to a higher level of accuracy * Metre rule – to measure the distance d Diagram: Where: * B is the optical bench with source holder, H * G is the Geiger-Mller tube * S is the decade scaler with variable EHT supply * R is the sealed radioactive source, cobalt-60 Cobalt-60 will be used as the gamma source as it is easily produced, by exposing natural cobalt to neutrons in a reactor, and therefore easy to acquire.15 It also produces ?-rays with energies of 1.17 MeV and 1.33 MeV. Method: 1. Clamp the G-M tube to one end of the optical bench and attach it to the input socket of the scaler 2. Set the variable EHT voltage on the scaler at a minimum and turn it on, allowing a few minutes for the scaler to warm up 3. Change the variable EHT voltage on the scaler to the value found through preliminary work and set it to count pulses from the G-M tube 4. Start the stopclock and measure the background radiation for an adequate length of time, e.g. 25 minutes, as background radiation is variable 5. Place the holder containing the ?-source at 5.0 cm from the window of the G-M tube 6. Start the stopclock and stop after 10,000 counts are registered. Record this value and repeat twice 7. Move the ?-source to 10.0 cm from the window of the G-M tube and repeat procedure 5, instead only counting 5000 counts 8. Move the ?-source to 15.0 cm from the window of the G-M tube and repeat procedure 5, instead counting only 1000 counts 9. Repeat procedure 7 for sets of 5.0 cm until a distance of 30.0 cm is reached 10. Tabulate these results and find the average count rate for each distance 11. Evaluate 1/(d + do)2 12. Using the recorded value for background radiation, evaluate the corrected count rate for each distance 13. Plot the graph of corrected count rate against 1/(d + do)2 References: 1 http://hyperphysics.phy-astr.gsu.edu/Hbase/forces/isq.html 2 Essential Pre-University Physics’ – Whelan & Hodgson, page 953 3 ‘Essential Principles of Physics’ – Whelan & Hodgson, page 472 4 ‘Essential Principles of Physics’ – Whelan & Hodgson, page 472 5 ‘Essential Principles of Physics’ – Whelan & Hodgson, page 472 6 http://www.imagesco.com/articles/geiger/03.html 7 http://en.wikipedia.org/wiki/Breakdown_voltage 8 ‘Essential Pre-University Physics’ – Whelan & Hodgson, page 406 9 http://www.imagesco.com/articles/geiger/03.html 10 http://en.wikipedia.org/wiki/Background_radiation 11 ‘Advanced Level Practical Physics’ – M Nelkon & JM Ogborn, page 218 12 ‘A Laboratory Manual of Physics’ – F. Tyler, page 269 13 http://en.wikipedia.org/wiki/Cobalt * 14 ‘Advanced Level Practical Physics’ – M Nelkon & JM Ogborn, page 212 15 http://en.wikipedia.org/wiki/Cobalt