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miss photon
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how does a transformer work?
arunbg said:http://en.wikipedia.org/wiki/Transformer" for an explanation of working and principles. In future, for complete explanation of concepts, start with your textbook or look for online resources.
First thing you have to know is that P = v^2/r, where 'v' is voltage dropped across the resistive load. Internal resistances across a high voltage power line tend to be small compared to the main load, and hence voltage dropped across them is far smaller. This becomes even smaller with higher voltages. Therefore 'v' becomes small and hence power dissipated is low. Note that this 'v' is not the entire voltage of the power line, but merely a small fraction of it. This is called voltage division.miss photon said:hey, thanks for the link. but i still have a doubt. for transmission of power, high voltages are used so as to reduce current in the wires. then power dissipation thru resistance would be i^2*R.but it can also be written as v^2/R. so what's the actual difference bwtn power supplied and power dissipated?
miss photon said:hey, thanks for the link. but i still have a doubt. for transmission of power, high voltages are used so as to reduce current in the wires. then power dissipation thru resistance would be i^2*R.but it can also be written as v^2/R. so what's the actual difference bwtn power supplied and power dissipated?
A transformer is an electrical device that is used to transfer electrical energy from one circuit to another through the principle of electromagnetic induction. It consists of two or more coils of wire, called windings, that are wound around a laminated iron core.
A transformer works by using the principle of electromagnetic induction. When an alternating current (AC) flows through the primary winding, it creates a changing magnetic field around the iron core. This changing magnetic field then induces a current in the secondary winding, which is connected to a different circuit. This allows the transfer of electrical energy from the primary circuit to the secondary circuit.
The two main types of transformers are step-up transformers and step-down transformers. A step-up transformer increases the voltage from the primary circuit to the secondary circuit, while a step-down transformer decreases the voltage. Transformers can also be categorized as either single-phase or three-phase, depending on the number of input and output windings.
The main components of a transformer include the primary and secondary windings, the iron core, and the insulation between the windings and core. The primary winding is connected to the source of electrical energy, while the secondary winding is connected to the load. The iron core is used to concentrate the magnetic field and improve the efficiency of the transformer.
The efficiency of a transformer is the ratio of output power to input power, expressed as a percentage. In an ideal transformer, the efficiency would be 100%, meaning all the electrical energy from the primary circuit is transferred to the secondary circuit without any losses. In real transformers, there are energy losses due to factors such as resistance in the windings and hysteresis in the core, leading to an efficiency of around 95-98%.