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Electricity & Megnetism

Difference between resistance and resistivity in tabular form

Resistance and resistivity difference                     Resistance                          Resistivity  It is the opposition to the flow of electric current through a conductor. It is the resistance of a meter cube of a wire. Its SI unit is ohm ( Ω ). Its ...

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Ammeter and voltmeter

An ammeter is an electrical device which is used to measure the current. It is the modified form of the galvanometer. It is a low resistance galvanometer. It is always connected in series with the circuit to measure current. An ideal ammeter has zero resistance. Meter movement The portion of galvanometer whose motion causes the needle of the device to ...

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Difference between electric and magnetic field

The difference between electric and magnetic field is that “Electric field is the area around the charged particles,it was introduced by Michel Faraday.While,magnetic field is the area or region around the magnetic where poles of magnet shows force of attraction or repulsion.More differences about electric field and magnetic field  are given in the comparison table below. Electric field Vs Magnetic ...

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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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