ELEMENT 2 - TECHNICIAN CLASS


Question Pool

SUBELEMENT T5 -- ELECTRICAL PRINCIPLES [3 Exam Questions -- 3 Groups] T5A Metric prefixes, e.g. pico, nano, micro, milli, centi, kilo, mega, giga; concepts, units and measurement of current, voltage; concept of conductor and insulator; concept of open and short circuits T5A01 (B)
If a dial marked in kilohertz shows a reading of 28450 kHz, what would it show if it were marked in hertz? A. 284,500 Hz B. 28,450,000 Hz C. 284,500,000 Hz
D. 284,500,000,000 Hz T5A02 (C)
If an ammeter marked in amperes is used to measure a 3000-milliampere current, what reading would it show? A. 0.003 amperes
B. 0.3 amperes C. 3 amperes D. 3,000,000 amperes T5A03 (C)
How many hertz are in a kilohertz? A. 10
B. 100 C. 1000 D. 1,000,000 T5A04 (C)
What is the basic unit of electric current? A. The volt
B. The watt C. The ampere D. The ohm T5A05 (D)
Which instrument would you use to measure electric current? A. An ohmmeter
B. A wavemeter
C. A voltmeter D. An ammeter T5A06 (B)
Which instrument would you use to measure electric potential or electromotive force? A. An ammeter B. A voltmeter C. A wavemeter
D. An ohmmeter T5A07 (A)
What is the basic unit of electromotive force (EMF)? A. The volt B. The watt
C. The ampere
D. The ohm T5A08 (C)
What are three good electrical conductors? A. Copper, gold, mica
B. Gold, silver, wood C. Gold, silver, aluminum D. Copper, aluminum, paper T5A09 (A)
What are four good electrical insulators? A. Glass, air, plastic, porcelain B. Glass, wood, copper, porcelain
C. Paper, glass, air, aluminum
D. Plastic, rubber, wood, carbon T5A10 (C)
Which electrical circuit can have no current? A. A closed circuit
B. A short circuit C. An open circuit D. A complete circuit T5A11 (D)
Which electrical circuit draws too much current? A. An open circuit
B. A dead circuit
C. A closed circuit D. A short circuit T5B Concepts, units and calculation of resistance, inductance and capacitance values in series and parallel circuits T5B01 (D)
What does resistance do in an electric circuit? A. It stores energy in a magnetic field
B. It stores energy in an electric field
C. It provides electrons by a chemical reaction D. It opposes the flow of electrons T5B02 (B)
What is the definition of 1 ohm? A. The reactance of a circuit in which a 1-microfarad capacitor is resonant at 1 MHz B. The resistance of a circuit in which a 1-amp current flows when 1 volt is applied C. The resistance of a circuit in which a 1-milliamp current flows when 1 volt is applied
D. The reactance of a circuit in which a 1-millihenry inductor is resonant at 1 MHz T5B03 (C)
What is the basic unit of resistance? A. The farad
B. The watt C. The ohm D. The resistor T5B04 (D)
What is one reason resistors are used in electronic circuits? A. To block the flow of direct current while allowing alternating current to pass
B. To block the flow of alternating current while allowing direct current to pass
C. To increase the voltage of the circuit D. To control the amount of current that flows for a particular applied voltage T5B05 (D)
What is the ability to store energy in a magnetic field called? A. Admittance
B. Capacitance
C. Resistance D. Inductance T5B06 (B)
What is one reason inductors are used in electronic circuits? A. To block the flow of direct current while allowing alternating current to pass B. To reduce the flow of AC while allowing DC to pass freely C. To change the time constant of the applied voltage
D. To change alternating current to direct current T5B07 (D)
What is the ability to store energy in an electric field called? A. Inductance
B. Resistance
C. Tolerance D. Capacitance T5B08 (A)
What is one reason capacitors are used in electronic circuits? A. To block the flow of direct current while allowing alternating current to pass B. To block the flow of alternating current while allowing direct current to pass
C. To change the time constant of the applied voltage
D. To change alternating current to direct current T5B09 (D)
If two resistors are connected in series, what is their total resistance? A. The difference between the individual resistor values
B. Always less than the value of either resistor
C. The product of the individual resistor values D. The sum of the individual resistor values T5B10 (A)
If two equal-value inductors are connected in parallel, what is their total inductance? A. Half the value of one inductor B. Twice the value of one inductor
C. The same as the value of either inductor
D. The value of one inductor times the value of the other T5B11 (C)
If two equal-value capacitors are connected in series, what is their total capacitance? A. Twice the value of one capacitor
B. The same as the value of either capacitor C. Half the value of either capacitor D. The value of one capacitor times the value of the other T5C Ohm’s Law (any calculations will be kept to a very low level – no fractions or decimals) and the concepts of energy and power, and; concepts of frequency, including AC vs. DC, frequency units, and wavelength T5C01 (C)
How is the current in a DC circuit directly calculated when the voltage and resistance are known? A. I = R x E [current equals resistance multiplied by voltage]
B. I = R / E [current equals resistance divided by voltage] C. I = E / R [current equals voltage divided by resistance] D. I = E / P [current equals voltage divided by power] T5C02 (B)
How is the resistance in a DC circuit calculated when the voltage and current are known? A. R = I / E [resistance equals current divided by voltage] B. R = E / I [resistance equals voltage divided by current] C. R = I x E [resistance equals current multiplied by voltage]
D. R = P / E [resistance equals power divided by voltage] T5C03 (C)
How is the voltage in a DC circuit directly calculated when the current and resistance are known? A. E = I / R [voltage equals current divided by resistance]
B. E = R / I [voltage equals resistance divided by current] C. E = I x R [voltage equals current multiplied by resistance] D. E = I / P [voltage equals current divided by power] T5C04 (C)
If a current of 2 amperes flows through a 50-ohm resistor, what is the voltage across the resistor? A. 25 volts
B. 52 volts C. 100 volts D. 200 volts T5C05 (B)
If a 100-ohm resistor is connected to 200 volts, what is the current through the resistor? A. 1 ampere B. 2 amperes C. 300 amperes
D. 20,000 amperes T5C06 (B)
If a current of 3 amperes flows through a resistor connected to 90 volts, what is the resistance? A. 3 ohms B. 30 ohms C. 93 ohms
D. 270 ohms T5C07 (C)
What term describes how fast electrical energy is used? A. Resistance
B. Current C. Power D. Voltage T5C08 (B)
What is the basic unit of electrical power? A. The ohm B. The watt C. The volt
D. The ampere T5C09 (A)
What happens to a signal’s wavelength as its frequency increases? A. It gets shorter B. It gets longer
C. It stays the same
D. It disappears T5C10 (A)
What is the name of a current that flows back and forth, first in one direction, then in the opposite direction? A. An alternating current B. A direct current
C. A rough current
D. A steady state current T5C11 (B)
What is the name of a current that flows only in one direction? A. An alternating current B. A direct current C. A normal current
D. A smooth current

END OF SUB-ELEMENT T5