GC: n CT: Electric current is the rate of charge flow past a given point in an electric circuit, measured in Coulombs/second which is named Amperes. In most DC electric circuits, it can be assumed that the resistance to current flow is a constant so that the current in the
GC: n CT: Unfortunately, when tree branches grow too close to the electric lines they can cause a power outage. Arcing or direct tree/wire contact is a major cause of power outages. In fact, a single tree/wire contact may deprive thousands of people of the electricity they need. If power
GC: n CT: Therefore, electricity is widely used in industries, establishments and in homes. Let us learn how the electricity we use at home comes from the electric power station. There are hydroelectric power stations (energy from water is converted into electricity), thermal power stations (energy from coal is converted
GC: n CT: What is an electric substation? Substations are a familiar sight alongside highways and in cities. Substations take the electricity from power plants and from the transmission lines and transform it from high to lower voltage. They distribute electricity to consumers and supervise and protect the distribution network
GC: n CT: Electrical energy is the energy carried by moving electrons in an electric conductor. It cannot be seen, but it is one of our most useful forms of energy because it is relatively easy to transmit and use. All matter consists of atoms, and every atom contains one
GC: n CT: Technology to utilise the forces of nature for doing work to supply human needs is as old as the first sailing ship. But attention swung away from renewable sources as the industrial revolution progressed on the basis of the concentrated energy locked up in fossil fuels. This
GC: n CT: Electricity generation is the first process in the delivery of electricity to consumers. The other three processes are electric power transmission, electricity distribution and electricity retailing. The demand for electricity can be met in two different ways. The primary method thus far has been for public or
GC: n CT: An electrolyser is a piece of scientific equipment that splits polarised molecules into its ions. In this case it will split water into hydrogen and oxygen gas. A dry cell electrolyser is an electrolyser that is completely enclosed; the other type is a wet cell electrolyser which
GC: n CT: Ionic substances contain charged particles called ions. For example, lead bromide contains positively charged lead ions and negatively charged bromide ions. Electrolysis is the process by which ionic substances are decomposed (broken down) into simpler substances when an electric current is passed through them. For electrolysis to
CG: n CT: Besides natural sources, the electromagnetic spectrum also includes fields generated by human-made sources: X-rays are employed to diagnose a broken limb after a sport accident. The electricity that comes out of every power socket has associated low frequency electromagnetic fields. And various kinds of higher frequency radiowaves
GC: n CT: Electricity can be static, like the energy that can make your hair stand on end. Magnetism can also be static, as it is in a refrigerator magnet. A changing magnetic field will induce a changing electric field and vice-versa (the two are linked). These changing fields form
GC: n CT: According to the theory quantum mechanics, an electron bound to an atom can not have any value of energy, rather it can only occupy certain states which correspond to certain energy levels. The formula defining the energy levels of a Hydrogen atom are given by the equation:
GC: n CT: Storage tanks are an important part of any distribution system. Water can be pumped into the tank during periods of low demand and then pumped out of the tank into the distribution system during periods of peak demand. In addition, storage tanks can provide the water pressure
GC: n CT: The story of Joseph Weizenbaum is in many ways almost as interesting as that of Turing. An early pioneer in computer science, Weizenbaum was one of the fortunate few to join the embryonic MIT Artificial Intelligence Lab in the early 1960s. His most celebrated accomplishment was the
GC: n CT: Any U.S. climate policy will have to be designed both to protect the earth’s climate by reducing emissions, and to protect American households from undue economic losses. Our model shows that these two objectives can almost be separated from each other. Roughly speaking, emission reduction depends on
CG: n CT: Although encrypted data appears random, encryption proceeds in a logical, predictable way, allowing a party that receives the encrypted data and possesses the right key to decrypt the data, turning it back into plaintext. Truly secure encryption will use keys complex enough that a third party is highly
GC: adj CT: The vast majority of the precipitation falling onto the land surface will eventually find its way back to the oceans via rivers, lakes or wetlands, or else be evaporated or transpired back into the atmosphere. There is one class of water-bodies, however, for which this journey is
GC: n CT: Physicists, who are scientists who study force, motion and energy, say that energy is the ability to do work, and work is moving something against a force, like gravity. There are a lot of different kinds of energy in the universe, and that energy can do different
GC: n CT: An energy balance usually refers to a year, and can be made for consecutive years to show time variations. Energy balances can be aggregate, or very detailed, depending on their functions. They can also be elaborate, showing all sorts of structural relationships between energy production and consumption,
GC: n CT: The population problem isn’t just a matter of the number of people. People consume food, fresh water, wood, minerals, and energy as we go about our daily lives. And producing food, pumping groundwater, harvesting wood, mining minerals, and burning fuel all deplete our resource base and produce
GC: n CT: Energy crops are grown specifically for use as fuel and offer high output per hectare with low inputs. Research into which strains perform best under UK conditions and typical outputs expected for different UK sites has been performed on a number of potential energy crops. S: BEC
GC: n CT: Energy density and the cost, weight, and size of onboard energy storage are important characteristics of fuels for transportation. Fuels that require large, heavy or expensive storage can reduce the space available to convey people and freight, weigh down a vehicle (making it operate less efficiently), or
GC: n CT: Over recent years, EU economies have been exposed to energy price increases leading to adverse effects on consumers and industries. Some economies have also been confronted with disruptions to gas supply, affecting gas-dependent industrial activities and households. Arguably, the EU economy will continue to be exposed to
GC: n CT: Energy efficiency is “using less energy to provide the same service”. There are other definitions, but this is a good operational one. The best way to understand this idea is through examples: When you replace a single pane window in your house with an energy-efficient one, the