Busy. Please wait.
or

show password
Forgot Password?

Don't have an account?  Sign up 
or

Username is available taken
show password

why


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.


Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
Don't know
Know
remaining cards
Save
0:01
To flip the current card, click it or press the Spacebar key.  To move the current card to one of the three colored boxes, click on the box.  You may also press the UP ARROW key to move the card to the "Know" box, the DOWN ARROW key to move the card to the "Don't know" box, or the RIGHT ARROW key to move the card to the Remaining box.  You may also click on the card displayed in any of the three boxes to bring that card back to the center.

Pass complete!

"Know" box contains:
Time elapsed:
Retries:
restart all cards
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

3E051 Set C Book 2

QuestionAnswer
We call anything that has weight and occupies space matter
Scientists can combine elements in either compounds or mixtures
According to the elctron theory, atoms are composed of protons, neutrons and electrons
Which statement best describes a positive ion? an atom that lost an electron and has more protons
What effect of current causes an electric motor to produce mechanical energy? Magnetism
Which of there is the smallest current that can be fatal under certain conditions? one-tenth of 1 amp
What moves a sufficient number of electrons to perform a useful job? voltage
A thermocouple produces voltage as a result of what type of energy? Heat
According to Ohm's law, how much voltage is needed to push 1 ampere of current through 1 ohm of resistance? 1 volt
What normally causes the resistance of a conductor to increase? increase in temperature
What is the unit of measurement for electrical power? watts
A 3-horsepower motor consumes how much power? 2.238 kW
We call a magnet that is magnetized by induction from an external source an artificial magnet
You can create a polarity and increase the strength of the magnetic lines of force around a conductor by looping the conductor into a coil
What items are required to construct an electromagnet? a coil of wire, a core material, and current flow
What are the two most common methods of producing voltage? chemical and mechanical
What are the three things needed to produce voltage by the principle of eletromagnetic induction? magnetic field, a conductor and relative motion
What type of current flow is the result of voltages produced by batteries and thermocouples? Direct current
What type of current flow cannot be transformed from a higher voltage to a lower voltage? Direct current
Which formula for finding the resistance of a circuit is correct? voltage divided by current
What is the resistance of a circuit with an applied voltage of 120 volts and a curent flow of 9 amperes? 13.33 ohms
How much current flow is in a circuit that has 24 volts applied and 72-ohms of resistance? 0.33 amperes
What is the current flow in a series circuit with a 20-ohm resistor, a 25-ohm resistor, and a 30-ohm resistor connected to a 25-volt power supply? 0.33 amperes
The total current in a parallel circuit is equal to the sum of the currents in the individual branches
The joint resistance of a parallel circuit is equal to the applied voltage divided by the total current
What is the joint resistance of a 5-ohm resistor and a 20-ohm resistor in parallel? 4 ohms
What is the joint resistance of a 4-ohm resistor, a 10-ohm resistor and a 12-ohm resistor in parallel? 2.3 ohms
What is the current flow in amperes of a circuit with an applied voltage of 120 volts and a power consumption of 600 volts? 5 amperes
What is the power in watts consumed by a circuit with 120 volts applied and a resistance of 12 ohms? 1200 watts
How many watts of power are present in a 5-ohm unit of resistance through which 2 amperes are flowing? 20 watts
How many rotations per minute (rpm) must a 2-pole generator rotate to produce 60 Hz? 3,600 rpm
What do we call the actual rating of alternating current (AC) power that is available to do work? effective value
How do we express the measurement of the apparent power of an alternating current (AC) electrical system? Kilovolt-amperes
What unit of measurement do we use in calculating the induction of a coil? Henry
Which formula do we use to calculate impedance in an alternating current (AC) circuit? Z=E/I
What is the capacitance of a 125 microfarad capacitor when we convert it to farads? 0.000125 F
The rules and equations for direct current (DC) circuits apply to alternating current (AC) circuits having only resistive load elements
Kirchoff's voltage law states that the algebraic sum around a closed loop must equal zero.
In an alternating current (AC) circuit, when current and voltage are out of phase, true power is less than apparent power
A 110-volt alternating current (AC) motor records 20 in-line amperes, and the in-line wattmeter shows only 1,936 watts being consumed. What would be the power factor of the AC circuit? 88 percent pf
What type of generator has brushes riding on the commutator to carry the current to an external circuit? DC circuit
What is the advantage of a having rotating magnetic field alternator? the output is taken from the stationary stator coils
A three-phase alternator normally receives power for its rotating magnetic field from a direct current (DC) generator
The voltage of a primary cell depends on the type of electolyte and the electrode material
A step-up transformer produced a secondary voltage that is higher and secondary current that is lower than the voltage and current in the primary
What does the word electronics mean? the control of electrons in motion
An electron is considered a free electron when it reaches the conduction band
A positive mobile charge is considered a hole
What determines whether an element is a conductor, an insulator or a semiconductor? the width of the forbidden band
External heat applied to electronic components causes increased current flow
Which condition exists when you connect the negative battery lead to a cathode? forward bias
Which of the following shows a proper electronic relationship? anode/p-type material
Which device should only be used in direct current (DC) circuits? Electrolytic capacitors
What does the tapered side on some diodes indicate? cathode
Which meter connection do we use to read forward bias on a diode? black lead to cathode
What does the arrow on electronic components indicate? The direction of hole current
What is a zener diode typically used for? voltage regulation
What is the key to the silicon controlled rectifier's (SCR) operation? gate
How do we label the electrodes on a transistors? Emitter, base, and collector
Which of the following are types of transistors? NPN and PNP
How does the base of a transistor normally recieve its control voltage? voltage divider circuit
In how many configurations can we connect transistors? three
What controls the conduction time of a silicon controlled rectifier (SCR)? gate current
What components make up a voltage divider circuit? resistors in series
Which component protects a silicon controlled rectifier (SCR) gate from reverse voltage? Diode
How do you turn off a silicon controlled rectifier (SCR) in a minimum amount of time? apply reverse bias to the anode
The five major classes of integrated circuit components are direct logic (DL), transistor-transistor logic (TTL), RTL, DTL, and DCTL
Both discrete and integrated seiconductor operations share the common problem of faulty connections
Which of the following is a logic gate? AND
Which of the following is not a logic gate? STOP
The load resistor of a half-wave rectifier serves two purposes-to develop the output signal and to limit current flow to a safe level
A full wave rectifier can be identified easily because it contains a center-tapped transformer
The breakdown rating for diodes in a full-wave rectifier must be twice as great as the half-wave rectifier
The average output voltage level of a bridge rectifier is equal to 0.636 peak input voltage
The output ripple frequency (pps) of a three-phase bridge rectifier is how many times the input frequency 6 times
The output of a three-phase rectifier is of low amplitude and requires little filtering
In a circuit powered by a rectifier, why does a ripple voltage exist? the rectifier supplies energy in pulses
An inductive (choke) input filter gives a lower output voltage than the capacitive input LC filter and also provides better voltage regulator
Which statement describes the characteristics of the Pi-type LC filter in comparison to the RC pi-type filter? High-output voltage and better voltage regulation
In the common emitter configuration, the input is between the emitter and base, and the output is between the collector and emitter
If we apply the positive alternation of an input signal to the base of an NPN transistor in a common emitter configuration, what does it cause? an increase in base current
The controlling element element in a common base configuration is the emitter
Which gain characteristic of a common base transistor amplifier is less than 1? current
Input resistance to a common collector amplifier is high because the emitter signal opposes the base signal
What purpose does the zener diode in the elctronic voltage regulator serve? sets the reference voltage
The output voltage of the electronic voltage regulator circuit can be adjusted to a specific value
What are the most common frequencies for transmission of electrical power? 50 Hz, 60 Hz, 400 Hz
One effect of high harmonic levels is misoperation of sensitive electronis
Which three pieces of equipment do we use most often to measure harmonics? wave analyzers, oscilloscope, spectrum analyzers
Which piece of equipment gives immediate qualitative information on the degree and type of distortion? oscilloscope
Created by: melissafish