When we discuss alternating current (AC) circuits, the term "phase" is crucial. Phase refers to the position of a point in time on a waveform cycle. If two waveforms, such as voltage and current, reach their maximum (positive peak) and minimum (negative peak) values at the same time, they are synchronized in their cycles.
Let's break down the given options:
A. Out of phase: This would imply that the peaks of the voltage and current do not align; there is a phase difference, meaning one reaches its peak before or after the other.
B. In phase: This means the voltage and current reach their positive and negative peaks simultaneously. They move together in the same direction at the same time.
C. Root mean square values: This term refers to a statistical measure of the magnitude of a varying quantity and is not related to the timing of peaks.
D. Power factors: This term describes the ratio of real power used to do work to apparent power flowing to the circuit. It's a measure of efficiency but does not describe the timing of peaks in the waveforms.
Given that the question specifies that voltage and current reach their positive and negative peaks at the same time, the correct answer must be that they are synchronized in their cycles. Therefore, they are said to be:
B. in phase
