Resistance of wire :: essays research papers

IF YOU INCREASE THE VOLTAGE - MORE CURRENT WILL FLOW. IF YOU INCREASE THE RESISTANCE - LESS CURRENT WILL FLOW (UNLESS YOU INCREASE THE VOLTAGE).' Ã ³`In Metals The Current Is Carried By Electrons 1. Electric current will only flow if there are charges, which can freely move. 2. Metals contain a sea of "Free Electrons" (which are negatively charged). And flow throughout the metal if they are given energy. 3. This is what allows electric current to flow so well in materials.' Ã ³`Resistance Resistance is anything that causes an opposition to the flow of electricity in a circuit. It is used to control the amount of voltage and /or amperage in a circuit. Everything in a circuit causes a resistance (even wire). It is measured in OHMS (Ω). Resistance occurs when the electrons travelling along the wire collide with the atoms of the wire. These collisions slow down the flow of electrons causing resistance. Resistance is a measure of how hard it is to move the electrons through the wire. The resistance of a wire depends on the number of collisions the electrons have with the atoms there will a larger number of collisions which will increase the resistance of the wire. If a length of a wire contains a certain number of atoms, when that length is increased the number of atoms will also increase. E.g. If there is a wire that is half the length of another wire it would also have half the number of atoms, this means that the electrons will collide with the atoms half the amount of times. Also if the length of the wire is trebled or quadrupled then the resistance would also treble or quadrupled.' My prediction was derived from this information. All of this information I collected originated from the Website, "www.studentcentral.co.uk" from encyclopaedias such as "The Oxford Children's Encyclopaedia" and computer encyclopaedias such as "Encarta". Ã ³This scientific information relates to my experiment by stating that the longer the lengths of wire the higher the resistance. Ã ³Preliminary Results Length Of Wire (mm): Voltage (V): Current (A): Resistance (Ω): Ã ³Therefore this information supports my prediction that the longer the length of wire the higher the resistance. Obtaining Evidence: Ã ³The variables I kept the same are: Ã ´The same material used for the wire, Ã ´The same cross-sectional area of wire, Ã ´And the same temperature of the wire. Ã ³The potential difference from the power pack: 2V.

Parliamentary vs Presidential Systems

The statement â€Å"The constraints imposed on a Prime Minister are greater than those imposed on a President. Therefore, a parliamentary system is more democratic than a presidential system†, makes a broad claim to which I agree. While Prime Ministers and Presidents are similar in some ways such as their responsibilities to do the best that they can for their nations, they also differ in many ways. These differences include separation of powers, the systems having different heads of state, and different election processes.Each of these examples contribute to the difference in constraints imposed on presidents and prime ministers and therefore contribute to the level of democracy within each system. A parliamentary system is â€Å"a system of governing in which there is a close interrelationship between the political executive (prime minister and Cabinet) and Parliament (the legislative or law-making body)† (Mintz, Close, and Croci 338), while a presidential system is d efined as â€Å"a system of governing in which the president and Congress each separately derive their authority from being elected by the people and have a fixed term of office† (363).Firstly, residential and parliamentary systems have different individuals as head of state and head of government (342). Presidents and prime ministers are considered to be heads of government, but while presidents are also heads of State, prime ministers are not. The head of state in a parliamentary system is symbolic, and â€Å"carries out a variety of official functions but is expected to be ‘above’ politics and thus is not usually involved in making governing for a country† (342).For example, in Canada the governor general, as a representative of the Queen, holds the role of head of state on a federal level, and the lieutenant-governors hold it on a provincial level. While these individuals do not have power in terms of law-making procedures and are not involved in elect ions or politics in general, the governor general does hold certain responsibilities and powers.The governor general is responsible for ensuring that a government is in place at all times and must approve of all legislation, but he/she also has certain powers that are higher in importance. The governor general can use personal discretion in situations such as the appointment and dismissal of the prime minister, and the dissolution of parliament or prorogation of parliament (343-344). On the other hand,

Effects Of Scurvy During The Middle Ages And The Age Of Sail

Imagine having swollen gums, tooth loss, fatigue, bruising, and exposure to new disease, only to die a few weeks after. With education, medicinal practices and accessibility to resources, the risk of scurvy proves less viable in our modern society. However, scurvy dominated the outbreaks and contributed to the onset of other pathogens during the Middle Ages and the Age of Sail. With over two million died during voyages, the disease impacted the ability to explore the world, the economy and ended up wiping out new colonies established from the Old World (Harthorne, 1). Caused by a lack of education, mundane conditions and diet, Scurvy became an epidemic between 1500 and 1800. Thus, scurvy ended up impacting the Columbian exchange and the role of history. Scurvy occurs as a result of a lack of Vitamin C for prolonged periods of time. Humans regularly use Vitamin C to perform vital function in the body. In the Age of Exploration, sailors went without any Vitamin C for upwards of a month due to a lack of education, inhumane conditions, and the spoilage time for fruits and vegetables. To get enough sailors to voyage across the world, captains and current workers would capture people to join their crew, never to see their families again. The captured faced deplorable conditions, including working vigorously for hours on end, limited sleep, rats crawling around and fecal matter around them. Stress levels increase due to the barbaric conditions they faced. Studies show that workersShow MoreRelatedCaptain James Cook5629 Words   |  23 Pagesprior to making three voyages to the Pacific Ocean, during which he achieved the first recorded European contact with the eastern coastline of Australia and the Hawaiian Islands, and the first recorded circumnavigation of New Zealand. Cook joined the British merchant navy as a teenager and joined the Royal Navy in 1755. He saw action in the Seven Years War, and subsequently surveyed and mapped much of the entrance to the Saint Lawrence River during the siege of Quebec. This helped bring Cook to theRead MoreAn Introduction to Hydrophonics and Controlled Environment Agriculture40110 Words   |  161 Pagesto 300 A.D. *600-500 B.C. – The â€Å"Hanging Gardens of Babylon† One of the seven wonders of the ancient world. Possibly one of the first examples of protected agriculture. Built by King Nebuchadnezzar II on the east bank of the Euphrates River in the middle of the desert for one of his wives. Renditions suggest a series of terraced growing areas in which water is supplied by a â€Å"chain pump† lift system from the river below. *Several hundred years B.C. – Egyptian hieroglyphs tell of the people growing