Ohm Law


Ohms law
The resistance of any material with a uniform cross-sectional area A depends on A and its length L , We can represent resistance in mathematical form

where  is known as the resistivity of the material in ohm-meters.
Ohm’s law states that at constant physical condition current through a resistor is directly proportional to the voltage across the resistor.

                                               i∝ v
Hence                                         v∝ i

                                              1Ω = 1V\A

 Good conductors, such as copper and aluminum, have low resistivity, while insulators, such as mica and paper, have high resistivity.

The circuit element used to model the current-resisting behavior of a material is the resistor.

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