Electric current is the time rate of charge, measured in .
A. watts
B. volts
C. joules
D. amperes
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The energy required to move a unit charge through an element is .
A. . current
B. . power
C. . voltage
D. . potential
The plus (+) and minus (-) signs in an electric circuit diagram are used to define .
A. . voltage polarity
B. . current direction
C. . power flow
D. . absorbed power
According to the passive sign convention, if the power has a plus sign, power is by the element.
A. supplied
B. absorbed
C. generated
D. transferred
Is current in any electric circuit always a constant-valued function? Why?