Chapter 35

The power factor for a capacitor is ___

0

The power factor for an inductor is

0

The power factor for a resistor is

1

Maximum power delivered by the source occurs at the resonant frequency. In this state, the impedance Z=

R

An emf source that reverses polarity periodically: ____ voltage source

ac

In general circuits with R, L, and C, the phase angle is

between -90 and 90

In a capacitor, the current lags the voltage

false

In a resistor, the current lags the voltage

false

In an inductor, the current leads the voltage

false

The quantity that gives an Ohm's Law like relationship between voltage and current in general R-L-C circuits:

impedance

As frequency decreases, capacitive reactance

increases

As frequency increases, inductive reactance

increases

Power loss in a circuit equals VI cos phi. The cos phi term is called the

power factor

The quantity that gives an Ohm's law-like relationship between voltage and current in inductors and capacitors:_________

reactance

________ occurs when inductive reactance equals capacitive reactance

resonance

Meters for use in ac circuits read the effective or ____ voltages and currents

rms

The reason rms values are used in circuit measurements is

rms values obey the same formulas for power gain or loss as in dc circuits

As frequency decreases, resistance

stays the same

A device for raising or lowering the voltage in an ac circuit:

transformer