unit 23

What is defined as a dramatic increase in voltage lasting 2 nanoseconds or less?

voltage spike

When calculating resonant frequency, in what units is inductance measured?

Henrys

In an RLC series circuit, _____ is the same through all components and the _____ are out of phase.

current; voltages

Because inductive and reactance and capacitive reactance are 180° out of phase with each other in an RLC series circuit, mathematical addition must be used to find their sum.

false

When calculating resonant frequency, in what units is capacitance measured?

farads

Voltage spikes and surges can travel to electrical equipment via what?

ground connection

If the applied voltage of an MOV is below its voltage rating, it exhibits a very __________ resistance.

high

When calculating resonant frequency, what does the value L represent?

indutance

What has its primary and secondary winding physically and electrically separated from each other?

isolation transformer

If an RLC parallel circuit contains more capacitive VARs than inductive VARs, the circuit has a _____ power factor.

leading

What is used to describe the amount of interference caused by an unwanted signal?

noise-to-signal ratio

When determining bandwidth, what does Q represent?

quality of bandwidth

When calculating values in an RLC parallel circuit, what does VARSC represent?

reactive power of the capacitor

What type of circuits are used to provide great increases of current and voltage at the resonant frequency?

resonant

Because inductive reactance and capacitive reactance are 180° degrees out of phase with each other, they __________from each other in an AC circuit

subtract

Capacitive reactance is measured in ohms.

true

In an RLC parallel circuit, the phase angle difference between the applied voltage and the total current is determined by the ratio of resistance, inductance, and capacitance connected in parallel.

true

Subtraction of the inductive reactance and capacitive reactance in an RLC series circuit, permits the impedance of the circuit to become less than either or both of the reactances.

true

The current flowing through a pure resistive element in an RLC parallel circuit will be in phase with the applied voltage.

true

When using vector addition for inductive reactance and capacitive reactance, the larger value is reduced by the amount of the smaller value.

true

When using vector addition for inductive reactance and capacitive reactance, the smaller value is eliminated.

true

If the power factor is corrected exactly so that the circuit is purely resistive, the power factor has a value of _____.

unity

In an RLC series circuit, the ratio of resistance, inductance, and capacitance determines how much the applied _____ leads or lags the circuit current.

voltage

In an RLC parallel circuit, the _____ is the same through all components and the _____ are out of phase.

voltage; currents

Because inductive reactance and capacitive reactance are _____ out of phase with each other, they subtract from each other in an AC circuit.

180 degrees

When power is applied to a capacitor, it begins to charge to the peak value of the ________.

appilied voltage

To correct the power factor to 100%, an equal amount of capacitive VARs would be connected in _____ with the motor.

parallel

When calculating values in an RLC parallel circuit, what does IL represent?

current flow through the inductor

During the period of time that the circuit is not at resonance, what is limited by the combination of inductive reactance and capacitive reactance?

current

As current increases, a magnetic field _________ around the inductor, inducing a voltage into the coil.

expands

Current can rise instantly through an inductor.

false

When determining bandwidth, what components result in a sharp increase and decrease of current?

high-Q components

If an RLC series circuit contains more capacitive VARs than inductive VARs, then the circuit has a _____ power factor.

leading

If the current leads the voltage in an RLC series circuit, the power factor is referred to as _____.

leading

What are designed to protect against much higher voltages and currents, such as lightning strikes?

lightning arresters

Capacitors help reduce or eliminate voltage spikes and surges by the current- limiting effect of a capacitor beingaffected by the frequency.

true

The impedance of the RLC series circuit is the sum of resistance, inductive reactance, and capacitive reactance.

true

When values of inductive reactance and capacitive reactance become equal, they are said to be resonant.

true

IR represents current flow through the inductor.

false

The current flowing through a pure inductive element leads the applied voltage by 90 electrical degrees.

false

When Ohm's law is applied to the RLC series circuit values, the voltage drops developed across the inductor or capacitor can be lower than the applied voltage.

false

If an RLC series circuit contains more inductive VARs than capacitive VARs, the circuit has a _____ power factor.

lagging