RESISTANCE

 

WHAT IS RESISTANCE IN AN ELECTRIC CONDUCTOR ?

Resistance of a conductor is it’s property to resist the flow of charges through it. Current flowing through a conductor is inversely proportional to its resistance.

Resistance is represented by the letter R or r

SI unit of resistance is ohm. 
Represented by Greek letter Ω

TYPE OF RESISTORS

Resistors are used in electric circuits and equipments for several useful purposes. Resistors are of two types fixed resistors and variable resistors 

Fixed resistors 


Material wires with fixed value of resistance and cannot be changed as it set to a specific value based on its length, area of cross-section and material used.

Variable resistors 



A resistor in which resistor in which resistance value can be adjusted according to the needs electric circuits or equipments is known as variable resistors.


RESISTANCE OF A SYSTEM OF RESISTORS

The current through a conductor depends up on its resistance and potential different (voltage) across its ends. In different Electric circuits resistance can be used in various combinations. There are two methods to combine resistance together.

1. Resistance in series 

2. Resistance in parallel 


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