ANSWERS WITH SOLUTIONS 2024
True - ANSWER Frequency is expressed as cycles per second, or Hertz (Hz).
True - ANSWER For current to flow through a circuit, the power source must apply enough electromotive
force (voltage) to cause electrons to flow.
True - ANSWER Current flow in an alternating-current circuit moves in both directions due to the
changing polarity of the voltage, whereas direct current flows only in one direction.
True - ANSWER When a magnetic field moves through a coil of wire, the lines of force of the magnetic
field cause electrons in the wire to flow in a specific direction. When the magnetic field moves in the
opposite direction, electrons in the wire flow in the opposite direction.
False - ANSWER A simple ac generator can be visualized as a loop of wire rotating within the magnetic
lines of force between similar poles of a magnet.
All of these - ANSWER The voltage produced by an ac generator is dependent upon the _____.
Current or voltage - ANSWER A waveform is a mathematical representation on a graph that can be used
to visualize the level and direction of _____ in a circuit.
True - ANSWER A pure direct-current waveform displays the polarity and magnitude of the current or
voltage as a flat waveform.
Any of these - ANSWER Most commercial alternating-current power is produced by a generator driven by
_____.
True - ANSWER The waveform for alternating-current circuits is symmetrical with positive above and
negative below the zero-reference level.
, Nonlinear loads - ANSWER A nonsinusoidal (or nonsymmetrical) waveform is produced when multiple
alternating-current waveforms of different frequencies are introduced on a circuit, typically by _____.
Phase - ANSWER When the term "_____" is used in relation to waveforms, it indicates the degree
relationship between two waveforms, such as voltage-to-current or voltage-to-voltage.
True - ANSWER Waveforms that are "in-phase" with each other means that at every instant, the current
is exactly in step with the applied voltage, and both the current and voltage waveforms reach their zero
and peak values at the same instant in time.
True - ANSWER A three-phase generator has each of its three windings evenly spaced around the rotor
and the windings are 120° out-of-phase from each other.
Voltage - ANSWER When describing the relationship between voltage and current waveforms, the
reference waveform (the one used to compare against) is the _____.
True - ANSWER A "lagging" waveform is when the voltage lags behind the current and a "leading"
waveform means the voltage leads the current.
Resistive - ANSWER A _____ load has its voltage waveform finishing its cycle at the same time (without
lead or lag) as the current waveform.
Inductive - ANSWER In circuits with _____ loads, the voltage waveform finishes its cycle before the
current waveform, so the voltage waveform "leads" the current waveform.
Capacitive - ANSWER In circuits with _____ loads, the voltage waveform finishes after the current
waveform so the voltage "lags" the current.
True - ANSWER Effective current value is also known as the "Root-Mean-Square" (RMS) value.
True - ANSWER Depending on the instant selected, the instantaneous value can range anywhere from a
zero, to a positive peak, or to a negative peak.