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Showing posts from December, 2009

TRANSFORMER

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Transformer What is a Transformer A transformer is an electrical apparatus designed to convert alternating current from one voltage to another. It can be designed to "step up" or "step down" voltages and works on the magnetic induction principle. A transformer has no moving parts and is a completely static solid-state device, which ensures under normal conditions, a long and trouble-free life. It consists, in it's simplest form, of two or more coils of insulated wire wound on a laminated steel core. When an alternating voltage is introduced to one coil, called the primary, it creates a fluctuating magnetic field in the iron core. This fluctuating field then induces an alternating voltage in the other coil, called the secondary or output coil. The change of voltage (or voltage ratio) between the primary and secondary depends on the turns ratio of the two coils. In the schematic shown V2 = V1 x N2/N1. Transformers are not limited to one output coil. Th

What is software

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SOFTWARE Computer software or just software is a general term used to describe the role that computer programs , procedures and documentation play in a computer system. The term includes: § Application software , such as word processors which perform productive tasks for users. § Firmware , which is software programmed resident to electrically programmable memory devices on board main boards or other types of integrated hardware carriers. § Middleware , which controls and co-ordinates distributed systems . § System software such as operating systems , which interface with hardware to provide the necessary services for application software. § Software testing is a domain dependent of development and programming. Software testing consists of various methods to test and declare a software product fit before it can be launched for use by either an individual or a group. § Test ware , which is an umbrella term or container term for all utilities and appli