When an AC source is connected across a resistor
Correct answer: B. the current and voltage are in phase
- A. the current leads the voltage
- B. the current and voltage are in phase
- C. the current lags behind the voltage
- D. any one of the above may be true depending upon the value of the resistance
Explanation
In a purely resistive AC circuit, such as when an AC source is connected across a resistor, the current and voltage are in phase with each other. This means that the peak of the current waveform occurs at the same time as the peak of the voltage waveform
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About Alternating Current
Alternating current varies periodically, so phase relationships become essential when current passes through a resistor, capacitor or inductor. The chapter distinguishes resistance from capacitive and inductive reactance, explains phase lead and lag, and connects changing electric and magnetic fields with the production and properties of electromagnetic waves.
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