Electrical Midterm 2A

An electrical circuit has a voltage of 50 V and a resistance of 5 Ω. What is the value of current?

10 Amps

A toaster is listed as 1560 W. When it is plugged into a 120 V circuit and starts to make toast, how many amperes will it draw?

13 Amps

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

339.46 V

What is the peak voltage of a 277 V RMS AC voltage?

391.68 Volts

Approximately how many horsepower is an electrical device listed as 3,000 watts?

4 HP

An electric motor is running on 120 V. The current is measured to be 2 A. How many ohms of resistance is the motor?

60 Ohms

An inductor has an inductive reactance of 64 Ω, and a wire resistance of 36 Ω. What is the impedance of the inductor?

73.4 Ohms (R^2+XL^2) (Square Root)

A capacitor can be thought of as a device that resists changes in current. Because a capacitor introduces reactance to the circuit, it shifts the current waveform to Lead Applied Voltage by _____.

90 Degrees

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

904.8 Ohms 2(3.14)FL

In a capacitor, the voltage difference between the plates controls the _____.

Amount of Current Flow through a Capacitor

One coulomb per second is equal to one _____.

Ampere

A test meter that uses a scale and pointer to indicate values is a(n) _____ meter.

Analog

What does Xc stand for?

Capacitave Reactance

Each complete waveform of 360° is called a _____.

Cycle

The material between a capacitor's plates is rated by a value called the _____.

DiElectric Constant

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

Effective

Polarized capacitors are also known as _____ capacitors.

Electrolytic

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

Frequency

The neutral conductor is also referred to as the _____ conductor.

Grounded

Frequency is measured in _____.

Hertz (Hz)

A voltmeter has a very _____ resistance connected in series with the meter movement.

High

The series ohmmeter is used to measure _____ values of resistance.

High

The total current-limiting effect is called _____.

Impedance (Z)

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

Inductance

What is L

Inductance of the Inductor

The symbol XL stands for _____.

Inductive Reactance

The velocity of AC through a conductor is _____ the speed of light.

Less Than

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

Linear

A(n) _____ ammeter operates on more than one range by connecting the meter movement to different shunts.

Multi Range

What meter measures resistance?

Ohm Meter

What meter must NEVER be connected to a circuit when the circuit power is turned on?

Ohm Meter

Square waves are generally produced by electronic devices called _____.

Oscillators

What meter measures an amount of voltage during a period of time and produces a two-dimensional image?

Oscilloscope

The maximum point of a waveform is called the _____.

Peak

The current-limiting property of an inductor is called _____.

Reactance

What causes a wire to become warm when current flows through it?

Resistance

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

An ammeter is connected in _____ with the load to permit the load to limit current flow.

Series

What type of circuit generally occurs when the conductors leading from and back to the power source become connected?

Short

Rotating machines normally produce a waveform called a _____ wave.

Sine

The _____ wave is a waveform that is symmetrical with positive above and negative below the zero reference level.

Sine

What is the most common of all AC waveforms?

Sine

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

The effective value is equal to the peak value _____.

Times 0.707

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

True

Of the different power values in an RL circuit, which one is known as quadrature power?

VARs

Of the different power values in an RL circuit, which one is known as wattless power?

VARs

The symbol for reactive power of an inductor is _____.

VARs

The amount of potential necessary to cause one coulomb to produce one joule of work is a(n) _____.

Volt

What meter is designed to be connected directly across the power source?

Volt Meter

What meter measures true power in a circuit?

Wattmeter

The symbol for reactance is _____.

XL

The Amplitude of a waveform is measured from _____.

Zero to the highest value obtained in either direction