Electricity 2 midterm

An RLC series circuit has an applied voltage of 240 volts. R = 48 Ω, XL = 100 Ω, XC = 36 Ω, and Z = 80 Ω. What is the reactive power of the capacitor?

324VARs

Two capacitors, a 20 μF and a 30 μF, are connected in series to a 400 Hz source. What is the total capacitive reactance?

33.16 ohms

What is the RMS value of an AC voltage that has a 480 V peak?

339.46V

The symbol for inductance is

H (henry)

The formula for Q is?

Q = mcT

The square root of the mean of the square of the instantaneous currents is known as the _____.

RMS

The current-limiting property of an inductor is called

Reactance

Dividing a circuit's total applied voltage by the total impedance results in the total_____.

current

A voltage _____ is used to provide different voltages between certain points in a circuit.

divider

The capacitive reactance of a capacitor is _____ proportional to frequency.

inversely

When a filter circuit offers little opposition to a frequency, the frequency is said to be

low pass

A band-rejection filter is one that

rejects a range of frequencies while passing frequencies on either side

To help overcome the problem of skin effect in high-frequency circuits, conductors with a large amount of _______________ must be used.

surface area

The amplitude of a waveform is measured from ____

zero to the highest value obtained in either direction

In a parallel circuit, ET = 120 V, R = 470 Ω, and XL = 500 Ω. What is the reactive power?

28.8 VARs

In a pure inductive circuit, current lags voltage by 90 degrees.

True

The symbol XL stands for inductive reactance

True

When AC voltage is rectified and converted into DC, the resulting waveform is normally not pure, flat DC. The pulses that occur are called ____.

ripples

LC parallel circuits are often referred to as ____ circuits.

tank

Name the three most common of all AC waveforms?

sine

Can AC and DC be transformed?

No

In a parallel circuit, ET = 120 V, R = 30 Ω, and XL = 40 Ω. What is IR?

4A

The number of cycles completed in one second is called a _____

Frequency

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

Lagging

What type of AC waveform features voltage rising at a constant rate with respect to time?

Linear

Square waves are generally produced by?

Oscillators

When a magnetic field continually changes magnitude and direction, a voltage is continually being induced in the coil. This voltage is called induced voltage.

True

A point that is used as a common connection for other parts of a circuit not actually driven into the ground is called a ______ ground

chassis

A term used to indicate the same value as the RMS value is the ____ value.

effective

When current rises and falls at the same rate as the voltage and reverses the direction of flow when the voltage reverses polarity, the current is said to be _____ with the voltage.

in phase

The_____ effect occurs when AC induces eddy currents into the conductor, which cause the electrons to be repelled toward the outer surface of the conductor.

skin

Two inductors are connected in parallel to a 120-V, 60-Hz supply. The values of the inductors are 1.5 H and 2.5 H. The total inductive reactance is?

1508 W

An inductor is connected to a 60 Hz circuit. The inductive reactance is 85.4 Ω. What is the inductance of the inductor?

0.2 H

An inductor with an inductance of three henrys (H) is to be connected to a 60 Hz circuit. What will the inductive reactance be?

1130.97 ohms

A three-resistor circuit has a total power of 25 W. Two of the resistors dissipate 10 W and 5 W, respectively. How much power does the third resistor dissipate?

10 W

An RLC series circuit has an applied voltage of 240 volts. R = 48 Ω, XL = 100 Ω, XC = 36 Ω, and Z = 80 Ω. What is the voltage drop across the capacitor?

144V

In a parallel circuit, ET = 240 V, R = 400 Ω, and XL = 300 Ω. What is P?

144W

What is the reactance of a 25 μF capacitor when the applied frequency is 400 Hz?

15.92 ohms

In a series RC circuit, ET = 240 V, R = 40 Ω, and XC = 30 Ω. What is ER?

192 V

What is the average voltage of a full-wave rectified 240 V RMS AC voltage?

216.17V

Two capacitors, a 20 μF and a 30 μF, are connected in series to a 60 Hz source. What is the total capacitive reactance?

221.04 W

Two inductors are connected in parallel to a 120-V, 60-Hz supply. The values of the inductors are 0.15 H and 0.225H. The total inductive reactance is

3.54 A

What is the peak voltage of a 279 V RMS AC voltage?

391.68

A μF capacitor has 2,652 Ω of reactance at 60 Hz. What is the reactance value at 400 Hz?

397.88 ohms

In a parallel circuit, ET = 120 V, R = 30 Ω, and XL = 40 Ω. What is IL?

3A

An inductor is connected to a 120-V, 60-Hz supply. The current in the circuit is 2.4 A. What is the inductive reactance?

50 ohms

What is the reactance of a 10 pF capacitor when the applied frequency is 30 Hz?

530.52 ohms

An RLC series circuit has an applied voltage of 277 volts. The current through the resistor is 3.5 A. What is the apparent power of the circuit?

969.5

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

Current, Voltage

Each complete waveform of 360° is called a _____

Cycle

The voltage rating of a capacitor _____.

DC rating

What is used to select one particular radio station from the thousands available?

Filter

What type of load contains pure resistance?

Resistive

Rotating machines normally produce a waveform called a _____ wave.

Sine

Circuits are generally considered to contain inductance when any type of load that contains a coil is used.

True

Frequency is measured in Hz

True

In a DC circuit, the product of volts times the amperes is called the ____ power.

True

What is the unit of measure for the power delivered to the load in a DC circuit?

Watts

What is the symbol for reactance

X

The voltage value that results is the _____ value if an AC waveform is rectified and converted into DC.

average

The maximum point of a waveform is called the _____.

peak