what work does transister,resistence,PF do in an electric circuit?
Transistor -
Transistor is a current producing device used in electronics.It consists of two p-n junctions back to back and is obtained by sandwiching either p-type or n-type semiconductor between a pair of opposite type of semiconductors.
It is used in radios, TVs, Computers etc.
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Resistor -
A resistor is an electrical component that implements electrical resistance as a circuit element.The current through a resistor is directly proportional to the voltage across the terminals of resistors.
Resistors are the most commonly used component in electronics which are used to create specified values of current and voltage in a circuit.They determine the flow of current in an electrical circuit and also they can be used with transducers to make sensor subsystems.