Assertion : Chock coil is preferred over a resistor to adjust cur… - Vidyadip

Question

Assertion : Chock coil is preferred over a resistor to adjust current in an ac circuit.
Reason : Power factor for inductance is zero.

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Answer

(a) If resistor is used in controlling ac supply, electrical energy will be wasted in the form of heat energy across the resistance wire. However, ac supply can be controlled with choke without any wastage of energy. This is because, power factor $(\cos \phi)$ for resistance is unity and is zero for an inductance. $[P=E I \cos \phi]$.

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