Medicine Manufacturing: Steps Involved and Types

Medicine Manufacturing: Steps Involved and Types Introduction: There are various types of medicines ranging from veterinary to medicines for human usage. Over the course of time, conscientious and diligent research has been put into improving the quality and effectiveness of medicines. There are hundreds of thousands of medicines available today meant for different ailments but this galore of medicines can be divided into three basic categories Tablets Syrups Gel Every medicine available comprises of two main constituents: Active ingredient and Additives/Excipients. The main remedy is the active ingredient. Whereas, the additives are added to inculcate rigidity, to increase the quantity so that the raw materials can be easily processed and to dissolve certain active ingredients. All human medicines that are produced on industrial scale must go through extensive testing and if its deemed fit for human usage it is produced commercially. There are various standards that are set to test the quality of medicines such as: European directorate for the quality of medicine (EDQM) and U.S pharmacopeial convention (USP). Tablet Manufacturing: In order to make the process more intuitive a specific product (Aspirin) will be discussed. 1. Raw materials: Phenol Sodium hydroxide Carbon dioxide Acetic anhydride Hydrogen Corn starch Water 2. Weighing: The corn starch, the active ingredient, and the lubricant are weighed separately in sterile canisters to determine if the ingredients meet pre-determined specifications for the batch size and dosage amount. 3. Mixing: The corn starch is dispensed into cold purified water, then heated and stirred until a translucent paste forms. The corn starch, the active ingredient, and part of the lubricant are next poured into one sterile canister, and the canister is wheeled to a mixing machine called a Glen Mixer. Mixing blends the ingredients as well as expels air from the mixture. The mixture is then mechanically separated into units, which are generally from 7/8 to 1 inches (2.22 to 2.54 centimeters) in size. These units are called slugs. 4. Dry Screening: Next, small batches of slugs are forced through a mesh screen by a hand-held stainless steel spatula. Large batches in sizable manufacturing outlets are filtered through a machine called a Fitzpatrick mill. The remaining lubricant is added to the mixture, which is blended gently in a rotary granulator and sifter. The lubricant keeps the mixture from sticking to the tablet machine during the compression process. 5. Compression: The mixture is compressed into tablets by a punch machine. On single-punch machines, the mixture is fed into one tablet mold known as dye cavity by a feed shoe, as follows: The feed shoe passes over the dye cavity and releases the mixture. The feed shoe then retracts and scrapes all excess mixture away from the dye cavity. A punch of the size of the dye cavity descends into the dye, compressing the mixture into a tablet. The punch then retracts, while a punch below the dye cavity rises into the cavity and ejects the tablet. The feed shoe returns to fill the dye cavity again, it pushes the compressed tablet from the dye platform. 6. Coating: Tablets may be coated to reduce swallow difficulties or target specific part of the body where the coating will dissolve and take effect. Coating is done by adding desired coating solution to the drum along with the tablets. Blowers are used to rapidly dry the coated tablets and prevent sticking. 7. Testing: The compressed tablets are subjected to a tablet hardness and friability test, as well as a tablet disintegration test. 8. Packaging: The tablets are transferred to an automated bottling assembly line where they are dispensed into clear or color-coated polyethylene or polypropylene plastic bottles or glass bottles. The bottles are topped with cotton packing, sealed with a sheer aluminum top, and then sealed with a plastic and rubber child-proof lid. A sheer, round plastic band is then affixed to the circular edge of the lid. It serves as an additional seal to discourage and detect product tampering. Syrup Manufacturing: 1. General manufacturing procedure: Syrups should be carefully prepared in clean equipment to prevent contamination. Three methods may be used to prepare syrups. Solution with heat Agitation without heat Percolation Although the hot method is quickest, it is not applicable to syrups of volatile ingredients. When using heat, temperature must be carefully controlled to avoid decomposing and darkening the syrup. Syrups may be prepared from sugars other than sucrose (glucose, fructose), non-sugar polyols (sorbitol, glycerin, propylene glycol), or other non-nutritive artificial sweeteners (aspartame, saccharin) when a reduction in calories properties is desired, as with the diabetic patient. The non-nutritive sweeteners do not impart the characteristic viscosity of syrups and require the addition of viscosity adjusters, such as methylcellulose. The polyols, though less sweet than sucrose, have the advantage of providing favorable viscosity, reducing cap-locking (which occurs when sucrose crystallizes), and in some cases acting as co-solvents and preservatives. 2. Cough syrup manufacturing process: Traditional cough mixtures are formulated around a syrup at 60-75% concentration which is made from sucrose, malt dextrin, glucose, invert syrup etc. The remainder is made up of thickening agents, stabilizers and active ingredients. Manufacturers of cough mixtures generally produce their own syrups as this offers greater control of product quality. The manufacturing process must achieve several functions: Dissolving of the sugars to form a syrup Hydration of powdered ingredients Blending ingredients of widely different viscosity Suspension or dissolving of active ingredients The end product must be smooth, agglomerate-free and homogeneous. High Shear mixer is used for mixing. Gel manufacturing Process: 1. Raw materials: Aluminium Acetate, Povidone Iodine, Propylene glycolCremophor RH 40, Lutrol F 127, Cetylstearyl alcohol, Cremophor A 6, Liquid paraffin, Parabene(s), Alpha-Bisabolol, Triethanolamine, Kollidon 30, Benzoyl peroxide, Betamethasone valerate etc. 2. Heating: The temperature should be high enough to ensure the intimate mixing of liquid phase and to prevent the premature crystallization and congealing of its components. Ointments preparation involves separate oil and water phases containing the required ingredients, heating each phase to between 60-70Â °C. 3. Mixing: Mechanical mixers, such as a steel jacketed kettle with agitator are commonly used to prepare semisolid preparations in pharmaceutical industry. The use of mechanical shear or a combination of fusion processes and mixing can be used to facilitate the dispersion or dissolution of the ingredients in the base to form a single-phase ointment. Time, temperature, and mechanical energy input are the three major variables in the manufacturing of semisolid preparations. 4. Emulsification: After the mixing process, the mixer is send to the emulsifier where the immiscible layers are forced to form an emulsion. 5. Cooling: Cooling rate can influence the final product quality. Different cooling rates after melting, mixing, and emulsification steps should be investigated as a process variable. The most important aspect of manufacture is to ensure all ingredients are fully dissolved and well mixed before packing and that the formulations contain suitable effective preservatives. Mixing is continued with cooling until the cream/gel is formed. 6. Packaging: After cooling, the gel is packed. In suspension, mixing of the bulk must be continued during packing to ensure even dispersion of the active ingredients at all times.

Neil Armstrong Essay -- Moon Flying Armstrong Biography Essays

Neil Armstrong When Neil Armstrong was two years old he loved going to the Airport to watch the planes take off and land. He got so excited just watching. When he was five years old he pretended that he was hovering over his bed. He wanted to fly! He loved airplanes and at six years old he had his first airplane ride. He was so smart in school that they moved him from second grade into third grade because he was reading at a fifth grade level. Every airplane book he got his hands on he read. He always liked building model airplanes. When Neil was in high school he worked in the Chemistry lab. In his basement he made a wind tunnel. And on the roof of his garage he built an observatory where he had telescopes to look at the moon and the stars. He learned so much and was so excited that he couldn't wait to fly. He worked in a pharmacy to pay for his flying lessons. When he was only sixteen years old he got his pilots license! He graduated high school and went to Perdue University on a US Navy scholars hip. He learned everything he could about planes and rockets. After college graduation he was a pilot in the Korean War. After the war he went back to Perdue to learn even more. He became a test pilot for experimental X-15 rocket planes which flew to the end of the earth's atmosphere. He didn't want to stop there, he wanted to just keep on going. So in 1962 when NASA was taking applications for astronauts he applied and was accepted. His first mission was on Gemini 8. He and D...

War as Transformation Essay -- Warfare Violence Essays

War as Transformation Many people look for reason in warfare. The reasons humans decide to kill each other are varied. Many wars start over land, difference of religion and culture, or economic stress. While there have been many wars over the years that man has inhabited this planet, World War I sticks out because of one incident that took place during the war. On December 25th, 1916 the Waring factions took essentially a "Christmas break" from their fighting, and went into enemy territory. They shared food and drink, and exchanged pictures of loved ones. They laughed and sang and tried to cross language barriers that the day before seemed insurmountable. The following day, they returned to their trenches, reinstated the boundaries of the war and began to fight anew. Even to this day, war is sometimes suspended for religious reasons, and no one finds this absurd or shocking. Recently, many Serbians were mad at President Clinton because he did not suspend bombing of Croatia during a holiday. As if war has a scheduled time and place. World War 1 was significant to this century because it was a war that involved peoples from practically every continent for the first time in history. It is ironic to think that the destructive force of war was something that , in a sense, brought many peoples of the world together for a common cause whether it w as the Allied cause, or the German or Russian cause. Looking at this war as an example of most wars, the causes of warfare stem from some sort of disagreement. Many of these disagreements derive from human insecurities about change. Fear of change drives people to hold tighter to their traditions and customs. When change is slow and progressive people may mutter under their breath, di... ...rks successfully. That is why people are so dependent on it. It is much easier to break someone's spirit with brute force than to use intellect and reason. War as a transformation process will continue unless people see that the same evolutionary processes of change in society can be implemented through negotiation. But these types of processes are slow and involve a willingness to be open to change. People have to get the idea in their head that change is inevitable, it is what life is based on. The status quo can not remain forever. It is only through this realization and openness to new ideas that war as a machine of progress can ever be stopped . Skilled leaders need to motivate people to negotiation, and to acting without aggression. To lose the 'us against them mentality' should be the ultimate goal of all societies and peoples. Every day should be Christmas.

The Welfare State

HISTORY OF THE WELFARE STATE: The role and significance of the Beveridge Report in establishing the Welfare State in Britain. The purpose of this essay is to look at the long history of the Welfare State in Britain and the evolving social, economic and political changes in society today, as well as the birth of the Welfare State after the Second World War which was the turning point (watershed) in British History.The freshly appointed Labour government by then took on the job of setting up a ‘welfare state’ that would systematically deal with the ‘five giant evils’ proposed by William Beveridge in a report, which later became known as the Beveridge report. The British welfare state, if it is to be defined, it is generally incorporated with Sir William Beveridge and the after war period.Welfare State is the concept in which government plays a key role in protecting and promoting the economic and social well-being of its citizens, based on the principles of eq ual opportunity in the distribution of wealth and public responsibility for those who lack the minimal provisions for a good life, for example good health, education and basic income (Abercrombie and Warde 2000). Is it the responsibility of a government to provide for its citizen, what about the cost, because it can lead to ever-increasing public spending that the government may find difficult to sustain.According to Abercrombie and Warde (2000) the term ‘welfare state’ was invented, following the Second World War when Social policy was developing. During the Second World War, the coalition government headed by Winston Churchill, the conservative party torch bearer deliberately planned the creation of a better Britain than the one in which many people have lived in the poverty-stricken 1930s.Plans were drafted and policies were generated which were to ensure that, in peacetime, there would be a family support system, good health care for all, more jobs will be made avai lable as well as creating new towns and adequate housing (Walsh et al, 2000). However, in 1941, during the Second World War, Sir William Beveridge was given a task by Winston Churchill (wartime prime minister of the coalition government) to head an interdepartmental committee of civil servants in an nvestigation and evaluate the national insurance policies as well as suggestions of ways to improve them (Addison, 2005). But, according to Walsh et al (2000) Beveridge went further than the original terms of references given him. In the final statement know as the ‘Beveridge report’ ( ), it was introduced by its architect, Sir William Beveridge, to the British parliament in 1942. Throughout this report, Beveridge kept mentioning the abolition of ‘want’ which was believed to be the major problem at the time.He predicted major reforms in health, housing, and education; because the policies needed to attack the five giant evils were set out in detail in his report . The five giant evils were want, disease, ignorance, idleness and squalor by which he meant poverty, unemployment, poor housing and lack of access to decent education and health care. This report was radical and became popular partly because of its promise of social security for all, and partly because it brings to mind the vision of the peacetime life promised by Winston Churchill at that time for which million were longing (Abercrombie and Warde 2000).Winston Churchill was not happy because the Beveridge report brought up issues which distracted people’s attention from the Second World War as well as threatening to produce controversy between the coalition governments. He also disapproved of the Beveridge report on the ground that no government could commit in advance the expenditure involved, thus, confusions between the Conservative and the Labour members and this affected his election champagne during the post war (Addison, 2005).William Beveridge recommendations based on social survey, were designed to tackle poverty primarily through the development of a national social security system, providing income security ‘from the cradle to the grave’( life -long) that will for the first time allowed the British people to have real income security that would be available to everyone regardless of means testing.As much as the ‘five giant’ differs from each other, there is a connection between the five of them, for example, unemployment in society causes people to lack financially and this can lead to lack of good medical care, want, poor housing and etc. The Five giant evils; Want, essentially this refers to poverty or lack, during the post war a lot of the British people were in need, they had no basic financial support and health care to keep them alive as well as keeping them above the poverty line by which income does not cover necessities.Due to lack of financial support people could not afford education and this resulted in lack of knowledge which is referred to as Ignorance, this was due to poor education. To make matter worst there was no national health care because, this had to be paid for, but there was no money and medical care was not free and this led to the outbreak of many diseases such as cholera, this was also linked to want, no money no medical care.Nevertheless, there were hospitals and only the rich in society could afford medical treatment, however, today the welfare state had made medical treatment available for all regardless of employment status. People were living in slums because there was poor housing and this was referred to as squalors, there is no difference today even though the welfare state has made provision for housing and some of these houses have been turned into slums by their occupant.Occupant of these houses don’t care to keep these houses clean because it cost them nothing, this giant is called Squalor, it is still with us today. The last giant was referred t o as Idleness, this was due to the hangover from depressions from the time of unemployment, today some people have chosen to stay idle, because the state will feed and house them. As much as the welfare state is good, the Victorian ‘workhouses’ would have been helpful in dealing with idleness in society, because one would need to work at the workhouse in order to get help from the state.The Beveridge report was an important document because it set out detailed policies for the attack needed to destroy the five giant evils, though the five giant evils were not destroyed completely, however, the Beveridge report left a legacy, the NHS and now there is nothing like absolute poverty in Britain as compare to the years before the Second World War when people use to actually sleep in slum, therefore the Beveridge report was a blueprint on which the welfare state was emerged because it helped shape Britain’s social policies. (Naidoo and Wills, 2008). The publication of t he Beveridge report was a great success.Majority of the British public welcomed the report’s finding and wished to see them implemented as quickly as possible according to an opinion poll (national archives, 2003). This shows the extent to which the population had shifted to the left wing (representing the Labour party) during the course of the Second World War. The post war election, in June 1945 resulted in a landslide victory for the Labour Party led by Clement Attlee , who promised in their election campaign that they will tackle Beveridge’s five giant evils and established ‘New Jerusalem’ which was reluctantly rejected by Winston Churchill.To implement the Beveridge’s report, the Labour party attacked the ‘five giant evil’ by passing legislations, though they were not completely destroyed, however, one of the giant called disease, the most famous tackled by the Labour government left the state with a legacy, the 1946 National Healt h Service Act which meant free accessible health care system for all beginning in 1948, though it was hugely expensive. In 1946 the national insurance act was passed to tackled the giant called ‘want’ making provisions for the unemployed and pregnant women, pension for the retired and etc.The education Act 1944, a conservative idea to tackle ‘ignorance’ so education was made free, the school leaving age was moved to 16 years previously 15. In 1947 Labour passed the education act into law. In 1948 the employment and training act was passed to tackle both ‘ignorance’ and ‘idleness’ making provision for school leavers , demobbed service men to train and established a skilled workforce. In addition, council house buildings and full employment was made possible by a better economy after the war. The five giants were tackled, but were not destroyed, because poverty has always lived with society.Comparably, there is nothing like absolute poverty in Britain today unlike before the welfare state when people had to make their homes in slums. Welfare states vary temporally as well as geographically. Like time welfare states do not stand still. Their evolution depends on choices made within restrictions (Powell, 1999). According to Marx (1999) welfare states make their own histories, but not within circumstances of their own choosing (cited in Powell, 1999). Today, the recommendations and policies that were detailed in the Beveridge eport to tackle poverty primarily through the development of a national social security system are still considered to provide the foundation of the modern welfare state References Lambert, T (2010). A Brief History of Poverty [online]. Available from: http://www. localhistories. org/povhist. html. [Accessed on 25th January 2011] National Archive (2003). The Welfare State [online]. Available from: http://www. nationalarchives. gov. uk/pathways/citizenship/brave_new_world/welfare. htm. [Access ed on 30th January 2011] Addison, P. 2005) Churchill The Unexpected Hero. New York: Oxford University Press. Abercrombie, N. And Warde, A. (2000) Contemporary British Society. Third Edition. Cambridge: Polity Press. Naidoo, J. and Wills, J. (2008) Health Studies An Introduction. Second Edition. Basingstoke: Palgrave Macmillan. Lowe, R. (1999) The Welfare State In Britain Since 1945. Second Edition. Basingstoke: Palgrave Macmillan. Powell, M. (1999) New Labour, New Welfare State? Bristol: Policy Press. Osborne, R. and Loon, B. V. (2004) Introducing Sociology. Cambridge: Icon Books Limited.

A Family of One Sound Essay

As we move forward through our lives we begin to see, new bonds created that makes this group a family. We speak together as one mind, one heart, one sound, so that love and support can be found. Our mistakes are learned from and we begin to look back, on the way things used to be before our music was intact. We cannot be a selfish a selfish generation only looking for fame, what we should realize is that at the end of every year we will never be the same. The truth about this group is that we leave no one out, and we all know to leave no doubt. Our parents always talk to us about setting the example for each other, what they don’t realize is that we are setting the example, for music, our other mother. Through the power of music everything is possible to us and we will not be denied, we need to take a stand and show everyone the power of ‘Jaguar Pride’. I am a witness as are you to the effect of one musician can have on us all, his memory reminds us that WE NEED TO STAND TALL. As our lives continue to change daily our bonds grow stronger, our music creates a common goal, to mourn no longer. My message through this spoken word is simple but everlasting; we should band together as one sound and persevere through our tragic passing. We’re the definition of putting up a fight, we have no weakness, and the ability to make our hardest times into positive memories is what will complete us. As we stand here today as witnesses to the power of music in our lives, we lay our foundation for starting a new, a new chance to strive. Think of me as a voice, a voice of support, my encouragement can be seen as a safe haven, a vocal fort. We often look past those things that are dearest to us, yet one thing stays common, the way music strengthens us. To say that we are one with music is just that, a saying, to be serious about this we must be one with ourselves and together as one unit, to show everyone we are staying. And to the choir directors, our loyal guardians, our second set of parents whom we love dearly, continue to be our guiding lights, our reason to not be weary. For all hardships and difficult situations that come our way, we all need to know that the three of you will stay with us always. I speak to you today through love and inspiration, to let you all, my other family know, that the power of music can help us obtain a new year of recreation that will always help us grow. Our main goal this year should be one that is simple, but always have a part of our heart; we must grow as one and show to everyone that one sound, for one reason, through one family is the purest art. Let us grow as one and support each other daily, we’ll show everyone that we truly are a family.

In the Dream of the Man that was Dreaming, the Dreamt Man Woke Essay

By traditional definition, perception is anything that can be known through the five senses. However, this quote adds another dimension to the idea about perception. It implies that perception is not dictated by the five senses, but by the brain. If a man perceives something, he has either seen it, heard it, felt it, smelt it, tasted it, or any combination of those. A man knows that a car has crashed because he saw the collision and heard the loud noise. He knows that he likes steak through enjoying its pleasant smell and satisfying taste. In addition, he knows that fire is hot because the nervous system allows him to feel its warmth. However, one usually forgets that it is impossible to use these senses without the brain, which controls each of these perceptions. The quote serves as a supporting reminder of this idea. Arguably, the dreaming man is able to perceive a dreamt man waking up. Yet, he does not necessarily see the man with his own eyes, because his eyelids are shut. He does not hear the dreamt man with his ears; he does not feel the man with his hands, and he certainly doesn’t taste or smell the man. So how is he able to perceive him? He is able to perceive him because his brain still functions, creating the image of the dreamt man waking. Now, the reason why the brain creates the image of the dreamt man is for another paper, about dream interpreting. The quote simply implies that we perceive only what our brain wants us to, and that our brain may even make us perceive what is not reality. It may be possible that we do not always know what is reality even if it is right in front of us. For example, today might feel like a cold day, yet it is still about 50-60 degrees F. However, in the winter months of January and February, a 60 degree day may not feel so cold. In fact, it would even feel warm compared to the usual freezing temperature. This is because the brain interprets what messages are sent through the nervous system, and it tells the body to feel warm because it is used to a colder temperature. Recently, due to the sniper shootings, America’s Most Wanted conducted a study which proved that the brain can affect what a witness may have seen with his or her own eyes. This is a major cause of the inconsistent eyewitness accounts of the shootings. These are just a few examples that prove that perception is under the complete control of the brain. Perception is much more than what the body is able to sense; it is how the brain interprets the information it receives through those senses. Even while the body is in slumber, the brain continues to interpret and create perceptions. Does the brain have a mind of its own?

Young’s Double Slit Experiment

Young’s double slits Formal Lab Florencia Shi Purpose: The double slits experiment was conducted to observe the interference of light waves, to explore how interference pattern would be affected by different colours, and to determine whether interference would change if the angle of slits was changed horizontally or vertically. Hypothesis: Dark and light bands would be seen, and red light causes wider nodal spacing, while blue light causes shorter nodal spacing. Materials: In this experiment, a lamp base assembly, a piece of blue filter, a piece of red filter, a slit plate, a laser pointer, a meter scale, and a 40 W lamp were used.Procedures: 1. A 40 W lamp was assembled in a lamp base assembly, and the assembly was settled on the edge of a desk top. 2. The lamp was turned on. And the filament of the lamp was seen, from a distance, by a person through the double slits on the slit plate. The shape of the interference was recorded. 3. A piece of red filter was placed in front of the lamp, and the lamp was seen, from a distance through the same double slits. The change of the interference pattern was recorded. 4.The filament of the lamp was seen by a student standing a certain distance away through the same double slits with a piece of blue filter placed in front of the lamp. The change of interference pattern was observed. 5. The slit plate was rotated vertically and horizontally, while other factors were kept constant. The change of interference pattern was observed. 6. The laser light conducted by the laser pen was directed through the double slits onto a piece of paper located 3m away. The interference pattern was observed through the slits. 7. The nodal spacing on that piece of paper was measured. 8.Step 6 and step 7 were repeated at a distance of 2m away. Observations: 1. The patterns of lamp light interference were dark and light bands, while the patterns of laser interference were dark and light spots. 2. After the red filter was placed in front of the lamp, the nodal spacing increased. After the blue filter was placed in front of the lamp, the nodal spacing decreased. 3. After the slit plate was rotated vertically, the light and dark bands were not parallel to each other any more, because after the slit plate was rotated vertically, the top and bottom of the double slits were not in the same vertical straight line.After the slit plate was rotated horizontally, the nodal spacing increased, because the distance between two slits (d) decreased. |Distance |? x1/2 |? x2 |? x3 |? x4 |? x5/2 |? xav | |(m) | | | | | | | |3m |0. 0022 |0. 0051 |0. 0049 |0. 0042 |0. 0025 |0. 0047 | |2m |0. 020 |0. 0048 |0. 0042 |0. 0039 |0. 0021 |0. 0043 | Discussion: 1. Dark and light bands were seen through the double slits. These were seen because the two lights came from the same source and had the same frequency. Therefore interference of light waves occurred. The light band was where two crests or two troughs intersected (antinodes), and the dark band was where a crest and a trough intersected (nodes). 2. A wider nodal space occurred in the interference pattern.Since when the lamp was blocked by the red filter, only red light could go through it, and the dark band occurs when the difference between the travelling distances of the two light waves is half of the wavelength. Since the red light has a longer wavelength, half of the wavelength increases accordingly, which means the dark bands will be more away from the central bright band. 3. The nodal space of the interference pattern decreased, since blue light has a shorter wavelength. 4. Blue has the shorter wavelength, and it was proved when the nodal spacing of the interference pattern became shorter. 5.After the slit plate was rotated vertically, the light and dark bands were not parallel to each other any more, because after the slit plate was rotated vertically, the top and bottom of the double slits were not in the same vertical straight line. After the slit plate was r otated horizontally, the nodal spacing increased, because the distance between two slits (d) decreased. 7. The pattern of laser interference consisted of light and dark spots, while the pattern of lamp light interference consisted of dark and light bands, because the light of the lamp could diffuse into a wider range of direction, while laser was ollimated, and was directed into a much narrower direction. 8. |Distance |? x1/2 |? x2 |? x3 |? x4 |? x5/2 |? xav | |(m) | | | | | | | |3m |0. 0022 |0. 0051 |0. 0049 |0. 0042 |0. 0025 |0. 0047 | |2m |0. 0020 |0. 0048 |0. 0042 |0. 0039 |0. 0021 |0. 0043 | 9. 1. Conclusion: Based on observations gathered during the experiment, the interference pattern of the 40 W lamp consisted of dark and light bands. When red filter was used, the nodal spacing of the pattern increased, and when blue filter was used, the nodal spacing of the pattern decreased. After the slit plate was rotated vertically, the light and dark bands were not parallel to each oth er any more. After the slit plate was rotated horizontally, the nodal spacing increased. The interference pattern changed into dark and light spots, after laser pointer replaced the lamp as a light source.The wavelength of the laser was predicted to be And the percentage of error calculated was Experimental Uncertainties: 1. The value of nodal spacing (? x) measured was not precise because the scale of a meter scale is only accurate to millimetres. 2. The slit plate was not exactly parallel to the screen that interference pattern was shown. 3. The measured nodal spacing (? x) was not precise due to the width of the slit. The d was only the distance between two slits, without including the width of the slit.