Question
What is the power factor for a purely inductive or purely capacitive AC circuit?
The correct answer is
0
In an AC circuit, power factor (PF) is defined as the cosine of the phase angle (ϕ) between the current and voltage. It is represented as:
PF = cos(ϕ)
1. In purely inductive or purely capacitive circuits, the phase difference between current and voltage is 90 degrees because:
- In a purely inductive circuit, voltage leads the current by 90°.
- In a purely capacitive circuit, current leads the voltage by 90°.
2. For a 90-degree phase difference, the cosine value is:
cos(90°) = 0
3. Therefore, the power factor for both purely inductive and purely capacitive circuits is:
0
Thus, the correct answer is 0.
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Important Questions from Power in Electric Circuits
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