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Electricity & Megnetism

what is Difference between motional and induced emf?

Motional EMF “The emf induced by the motion of a conductor across a magnetic field is called motional emf”. In the previous section we have studied that when conductor is moved across a magnetic field, an emf induced between its ends. The emf of the moving conductor is similar to that of a battery,i.e., if the ends of the conductor ...

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Difference between amplitude modulation and frequency modulation

What is modulation? Until the process of superimposing a low frequency (long wave) voice information component on a high frequency (short wave) carrier signal was perfected,the most widely used form of communication was a system based on the transmission of a continuous wave (CW) signal.With this system,the signal was interrupted periodically (Morse code) to produce a coded message.The CW system ...

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Different types of motors and their applications

What is Electric Motor? An electric motor is an electromechanical device that converts electrical energy into mechanical energy.Electrical motors can be run as generators and vice versa, although this is not always practical. What is the working principle of electric motor? When a current-carrying conductor is located in an external magnetic field perpendicular to the conductor, the conductor experiences a ...

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How materials are magnetized and demagnetized?

What are Magnets? A permanent magnet has a magnetic field surrounding it. A magnet field can be envisioned to consist of lines of force that radiate from the north pole (N) to the south pole (S) and back to the north pole through the magnetic material. A permanent magnet, such as the bar magnet has a magnetic field surrounding it that ...

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Different types of transducers and their applications

What are transducers? “A transducer is an electronic device that converts energy from one form to another.”Common examples include microphones,loudspeakers,thermometers,position and pressure sensors and antenna.Although not generally thought of as transducers,photocells,LEDs,and even common light bulbs are transducers. Efficiency of transducer Efficiency is an important consideration in any transducer.Transducer efficiency is defined as:”The ratio of the power output in the desired ...

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Uses and examples of electromagnetic waves in everyday life

What are Electromagnetic Waves? Electromagnetic waves are defined as:” Waves which requires no medium for transmission and which rapidly propagates through vacuum.”radio waves,television waves,X-rays light rays etc,are the examples of electromagnetic waves. History of electromagnetic waves in physics In 1864 British physicist James Clark Maxwell formulated a set of equations known as Maxwell’s equations which explained the various electromagnetic phenomena. ...

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What is transformer,types,applications & working principle

“A transformer is an electrical device to change a given alternating emf into a larger or smaller alternating emf.”or “It is a static or stationary piece of apparatus that transfers electric power from one circuit to another having mutual inductance without changing the frequency.”A basic transformer is an electrical device constructed of two coils placed in close proximity to each ...

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5 band resistor colour code table and chart

Carbon resistors are most common in electronic equipment.They consists of a high grade ceramic rod or cone ( called the substrate on which is deposited a thin resistive film of carbon. The numerical value of their resistance is indicated by a colour code which consists of bands of different colors printed on the body of the resistor.The color used in ...

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structure of atoms and molecules with examples

what is Atom? “Atom is the smallest particle of an element that possesses the unique characteristics of that element.”All matter is composed of atoms;all atoms consists of electrons,protons, and neutrons except normal hydrogen,which does not have a neutron.Each element in the periodic table has a unique atomic structure,and all atoms within a given element have the same number of protons.At ...

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Potentiometer definition types and uses

What is potentiometer? “A potentiometer is a very simple instrument which can measure and compare potential differences accurately”.Potential difference is usually measured by an instrument called a voltmeter. The voltmeter is connected across the two points in circuits between which potential  differance is to be measured. It is necessary that the resistance of the voltmeter be large compared to the ...

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