Question

Draw and impedance diagram of a series LCR circuit and write the expression for
the power factor from the diagram.

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Answer 1

Explanation:

Thus far we have seen that the three basic passive components of: Resistance, Inductance, and Capacitance have very different phase relationships to each other when connected to a sinusoidal alternating supply.

In a pure ohmic resistor the voltage waveforms are “in-phase” with the current. In a pure inductance the voltage waveform “leads” the current by 90o, giving us the expression of: ELI. In a pure capacitance the voltage waveform “lags” the current by 90o, giving us the expression of: ICE.

This Phase Difference, Φ depends upon the reactive value of the components being used and hopefully by now we know that reactance, ( X ) is zero if the circuit element is resistive, positive if the circuit element is inductive and negative if it is capacitive thus giving their resulting impedances as:

Element Impedance