In an a.c. circuit with phase voltage V and current
I, the power dissipated is
- V.I
- depends on phase angle between V and I
- $\frac{1}{2}\times V.I$
- $\frac{1}{\sqrt2}\times V.I$
The Correct Option is B
Solution and Explanation
$(P)=V\times I \times cos \, \theta$.Therefore current flowing in
the circuit depends upon the phase voltage (V)
and current (I) of the a.c. circuit.
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Concepts Used:
Reactance
Reactance is the measure of the opposition of inductance and capacitance to current in an AC circuit which is denoted by X. It varies with the frequency of electrical signals and is measured in ohms.
Types of Reactance:
- Capacitive reactance ( XC), and
- Inductive reactance ( XL ).
The formula of Reactance:
The total reactance (X) is equal to the difference between the two:
Total reactance, X = X
a. Capacitive Reactance (XC) is the reactance, which is large at low frequencies and small at high frequencies.
b. Inductive Reactance, (XL) is the reactance which is small at low frequencies and large at high frequencies.