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Renewable and non renewable energy source examples
Short paraghraph topic alternative source of energy
Renewable and non renewable energy source examples
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All useful generators of electricity come in two basic forms, alternating current and direct current. Direct current (dc) comes from generators that do not change in polarity, always producing a positive charge. In alternating current (ac) the polarity of the terminals is always changing from positive to negative. Thus you are left with alternating current flow. There are different ways of measuring and generating alternating and direct current.
Direct current only flows in one direction in a circuit. Because the polarity of a direct current voltage source is always the same the flow of current never changes direction. Batteries are one of the more common direct current voltage sources. Batteries are good because their voltage is fixed as well as their polarity. Direct current dose not always need to a constant voltage but it must always stay traveling in the same direction. There are such direct currents called varying and pulsating that change value but not direction.
Alternating current is always changing in direction and amplitude. The current flow in alternating current changes in even intervals. Ac usually changes in power and direction. The vast majority of power supplied for households and big business is alternating current. This is because of the ease of generating alternating current in alternators. The main concept of alternators is moving a conductor through magnetic lines. The change in the magnetic field around the conductor or vice versa makes electrons move. When you have physically moved either the conductor or magnet in a complete 306-degree circle you have produced one sine wave or one complete cycle. The amount of time it takes to complete one cycle is referred to as a period. The frequency of an alternating sine wave is the amount of cycles per second. Frequency is measured in hertz. One hertz is equivalent to one cycle per second. The frequency coming out of your electrical plug at home is 60 Hz. The peak value in a sine wave is the top voltage level away from zero. The peak-to-peak voltage value is referring to difference between the positive peaks value to the negative peak value. The effective or rms value of a sine wave is the actual amount you would use or measure using a multi-meter. In three-phase alternating current there are three different coils or conductors that produce three different sine waves.
The module AC/DC is directly related to the career path of the electrical linemen. In the module i learned about two types of electrical current, alternating (AC), and direct current (DC). In direct current (DC), the electric charge (current) only flows in one direction. Electric charge in alternating current (AC), on the other hand, changes direction periodically. The voltage in (AC) circuits also periodically reverses because the current changes direction. Electrical lineman work on power lines and other thing that have (AC) or (DC) current depending on what they are working on. Lineman work on electrically energized (live) and de-energized (dead) power line. They may perform a number of tasks associated with power lines, including installation or replacement of distribution equipment such as capacitor banks, distribution transformers on poles, insulators and fuses.
A battery is a device which converts chemical energy into electrical energy. A battery usually consists of two or more cells connected in series or parallel, you can also have a single cell battery. All cells consist of a positive electrode, and a negative electrode. An electrolyte is a liquid substance capable of conducting electricity. In this substance one of the electrodes will react producing electrons, while the other will except electrons. When the electrodes are connected to a device to be powered, called a load, an electrical current flows.
· B-phase transformer (EMTU-TT01) · Feedback electronic wattmeter · Multi-range moving-iron ammeter · Instrument voltage transformer THEORY AND INTRODUCTION ----------------------- Transformers are used all over the world to step-up and step-down electricity. The transformer is one of the most commonly used electrical devices. The reason the transformer is so popular is because they range in size from 240V to well over 240kV, stepping -up and stepping-down electricity all over the world.
In New York City during the late 1880’s, a fierce battle was raging between two great innovators of the age. The combatants, Thomas Edison and Nikola Tesla, were fighting over the prize to power cities in the ever more industrial world. Thomas Edison championed his direct-current (DC) system whereas Nikola Tesla was proposing his system using alternating-current (AC). This “War of the Currents” ushered in the electrical age, from which our modern society arose. Just as the AC and DC electrical generating systems where diametrically opposed to each other; so were Nikola Tesla and Thomas Edison.
v+Vmaxsin(angular position of coil)”(cookeadamsdellmoore pg 509). This hopefully adds some insight into the use of electric motors, and the principles that make these motors work. Such as electromagnetism, binary switches for DC motors, and the selection of a running frequency of a motor through the use of an oscillator.
Have you ever walked into a room, turned on a light, and wondered, “Who gave us the ability to do this?” Nikola Tesla is the man’s name. He invented Alternating Current, or AC, which is the electrical system that we use to power our world today. In this paper, I will be describing a few of Nikola Tesla’s innovations and how they inspired and impacted our way of life.
In this paper, I will talk about how AC circuits can be described by considering voltage and current using complex numbers. An AC circuit requires two separate numbers to be able to completely describe it. This is because it takes into account the amplitude and the phase of the current. The fact that complex numbers can be easily added, subtracted, multiplied or divided with each other makes them ideal for this operation where both amplitude and phase have to work together.
When Tesla stepped foot in New York he came with the idea of alternating current, drawing his dea in the sand . To get his start he went to work for Edison who was working with direct current at the time. Edison took advantage of Tesla which lead to the “Battle of the Currents”. Edison invented the direct current which was very popular in its day and is still used. Direct current created a very dim light and could only travel for two miles. With this short distance, many power stations had to be built (A&E Television Networks). When Tesla came to America, in 1884, he worked on machines for Edison in his power stations. Tesla did not stay with Edison and quit soon after Edison refused to pay him for his work. Tesla said “I predict that very shortly the old-fashioned incandescent lamp, having a filament heated to brightness by the passage of electric current through it, will entirely disappear,” (“Tesla Universe”). By predicting this, he made alternating current better and more efficient than Edison’s direct current. It could travel for hundreds of miles, and created a bright light which was the total opposite of direct current. Alternating current was purchased from Tesla by Westinghouse for over 1 million dollars (William Harris). When Westinghouse took over, the popularity of alternating current skyrockete...
From these batteries, the electricity goes to an inverter, which then changes the DC to AC or alternating current in order to use our modern electrical appliances and gadgets. There are two types of grid systems, which operate off solar panels, “off-grid” or “grid-tied”. My mom chose an off-grid system, which means we are independent of the public utility grid, DMEA, and don't have to pay any electrical bills and, if there’s sun, there’s always power.... ... middle of paper ... ...
As a graduate student, I will undertake research and coursework in Electrical Engineering to enhance my competencies in this field. I intend to complete my master's degree in order to pursue my doctorate. The research that I am most interested in pursuing at Northeastern University surrounds the optical properties of MEMS devices, and the development of substrate-based fast electro-optical interfaces. My interest in this area stems from my undergraduate study in MEMs development for tri-axial accelerometers.
Electrical Engineers research, develop, design, and test electronic components, products, and systems for commercial, industrial, medical, military, and scientific applications (Cosgrove 749). They are concerned with devices that use small amounts of electricity that make up electronic components such as integrated circuits and microprocessors. By applying principles and techniques of electronic engineering they design, develop, and manufacture products such as computers, telephones, radios, and stereo systems (EGOE, 121). Electrical engineers touch everyone lives through the things they have designed or created. Electrical engineers have invented the lights in your house, the television, the stereo, the telephone, computers, and even your doctor’s blood pressure gauge (Stine 300).
V(voltage) I (current) Therefore, I = V R Therefore, if V is constant, in order to increase I, R must decrease.
The stator is the stationary component while the rotor is the rotational component of the motor. Usually magnetic fields are created when an electric current is applied to a set of conductive wires wound together (Dixon, 2001). Magnetic fields can also be created using Permanent Magnets (PM). Electrical motors can also work as electrical generators (Correla, 1986). Electrical generators are devices capable of converting mechanical energy into electrical energy. An example would be a wind turbine which works as an electrical generator. It converts the mechanical energy of the rotating shaft caused by wind into electrical energy (Correla, 1986). The focus of this research will ...
Consider a material, either a semiconductor or conductor as shown in the below figure. When voltage is applied, electric current starts flowing in the positive x direction (from left to right). If a magnetic field is applied to this current carrying conductor in a direction perpendicular to that of the flow of current (that is z direction), an electric field is produced in the conductor that exerts force in the negative y direction (downwards).
Power equals influence. It 's personal, too, residing within those who wield it. Sometimes a position of authority within an organization lends power to a person, but borrowed power isn 't necessarily as effective as power derived from leadership. Every organization has leaders who hold no positional authority, yet somehow wield influence, while managers who should be able to command respect flounder. Small-business owners wanting to enhance their influence and that of their managers should consider the five sources of power available at organizations. Three come with position. The other two are available to anyone.