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Electricity & Megnetism

Types of magnetic materials with examples

There are three types of magnetic materials.Examples of magnetic materials are: Paramagnetic materials Diamagnetic materials Ferromagnetic materials Paramagnetic substances paramagnetic substances are those which are attracted by magnets and when placed in a magnetic filed move from weaker to stronger parts of the field. Paramagnetic materials examples Familiar examples are: aluminum maganese platinum, crown glass solution of salts of iron ...

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Semiconductors and superconductors

Difference between semiconductors and super conductors is that semiconductors are the materials that have properties lie between conductors and insulators,while super conductors are those materials that act strangely when cooled down. Semiconductors Semiconductors are those materials which are neither good conductors nor good insulators.Their conductivity is intermediate between conductors and insulators.Silicon and germanium are semiconductor elements, at room temperature.The conducting ...

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Inductance of a solenoid derivation

Inductance of a solenoid Now we will prove “Inductance of a solenoid derivation”. Consider a solenoid having n turns per unit length.When current passes through the solenoid, magnetic field is produced inside the solenoid which is directed along the axis of the solenoid.The magnetic field in space outside the solenoid is so weak that it is considered zero. The inductance ...

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Kirchhoff’s voltage and current law with examples

What is Kirchhoff’s Voltage Law? Kirchhoff’s voltage law is a fundamental circuit law that states that the algebraic sum of all the voltages around a closed path is zero or, in other words,the sum of the voltage drops equals the total source voltage. Kirchhoff’s loop rule In an electric circuit, the voltages across the resistors(voltage drops) always have polarities opposite ...

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Joules law of heating equation

 State Joule’s law of heating “The heat produced in a conductor is: (1) Directly proportion the square of current passing through the conductor,(H ∝ I²) keeping R and t constant; (2) Directly proportion to the resistance of the conductor (H ∝ R) keeping I and t constant;and (3)Directly proportional to the time of flow of current (H ∝ t) keeping I and R ...

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Energy stored in a capacitor equation derivation and problems

Energy stored in a capacitor equation Consider a capacitor with the capacitance ‘C’ ,which is connected to the battery of emf ‘V’ .If ‘dq’ charge is transferred from one plate to other,then the work done ‘dW’ will be: dW =V dq This work done is stored in the form of electric potential energy ‘dU’ dU =V dq When the capacitor ...

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Difference between polar and non polar dielectric materials

Capacitance with dielectric formula Consider a parallel plate capacitor which is connected with a battery of emf ‘V’ .Let ‘A’ is the area of each plate and ‘d’  is separation between the plates. If ‘q’ charge is stored in the capacitor when there is vacuum or air as medium between the plates ,then: q= CV Where ‘C’ is the capacitance ...

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formula for total capacitance in series and parallel combination

Formula of equivalent capacitance in series Series combination when capacitors are connected in series,the total capacitance is less than the smallest capacitance value because the effective plate separation increases.The calculation of total series capacitance is analogous to the calculation of total resistance of parallel resistors. This type of combination has the following characteristics: Each capacitor has the same charge across ...

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Inductor and inductance:types and applications

What is Inductor and what does it do? When a length of wire is formed into a coil,it becomes a basic inductor. The term coil and inductor are used interchangeably.Current through the coil produced an electromagnetic field, as illustrated. The magnetic lines of force around each loop (turn) in the winding of the coil effectively add to the lines of ...

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Magnetic flux density:Definition,unit,formula and applications

magnetic flux

Magnetic Flux definition The group of force lines going from the north pole to the south pole of a magnet is called the magnetic flux, symbolized by Φ (the Greek letter phi). The number of lines of force in a magnetic field determines the value of the flux. The more lines of force, the greater the flux and the stronger the magnetic ...

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