Deck 2: The Fundamentals of Electricity

Question 1

Protons are attracted to other protons and repel electrons.

Answer 1

False

Question 2

An atom must always have an equal number of protons and electrons.

Answer 2

False

Question 3

Copper is a good conductor of electric current because it has eight or more electrons in its valence band.

Answer 3

False

Question 4

Increasing the voltage causes the electric current flowing through a fixed value of resistance to increase.

Question 5

Increasing the resistance while keeping the voltage source held at a fixed value causes the electric current flowing through the resistance to decrease.

Question 6

Voltage is most like which of the following:

A) Restriction
B) Pressure
C) Flow rate
D) Temperature

Question 7

Technician A says that an ohmmeter can be used to measure voltage drop. Technician B says that an ammeter can be used to measure current. Who is correct?

A) A only
B) B only
C) Both A and B
D) Neither A nor B

Question 8

Which is most like electric current?

A) Restriction
B) Pressure
C) Flow rate
D) Temperature

Question 9

Technician A says that the conventional theory describes electric current flow from negative to positive. Technician B says that current is measured in units of amperes per second. Who is correct?

A) A only
B) B only
C) Both A and B
D) Neither A nor B

Question 10

Which is the correct equation for Ohm's law?

A) Voltage/Resistance = Current
B) Current × Resistance = Voltage
C) Voltage/Current = Resistance
D) All of the above are valid expressions of Ohm's law.

Question 11

Which of the following is the largest value of pressure measured at sea level?

A) 14.7 psi absolute (101 kPa absolute)
B) 14.7 psi gauge (101 kPa gauge)
C) -14.7 psi absolute (-101 kPa absolute)
D) All of the above are the same value of pressure.

Question 12

A voltmeter that is being used to measure a voltage drop across a resistor is most like which of the following?

A) A differential pressure gauge measuring the pressure drop across a hydraulic circuit restriction
B) A flow meter measuring the rate of hydraulic fluid flow
C) Two pressure gauges measuring the pressure in a hydraulic circuit referenced to atmospheric pressure
D) An ohmmeter measuring the resistance in an electric circuit with current flowing through the circuit

Question 13

Referring to the following circuit, technician A says that 12V would be dropped across R1 and R2. Technician B says that the same amount of current will flow through R1 and R2. Who is correct?

A) A only
B) B only
C) Both A and B
D) Neither A nor B

Question 14

Which of the following is a true statement regarding the circuit shown below?

A) The amount of current flow through R1 is equal to the current flow through R2 added to the current flow through R3.
B) The voltage dropped across R2 is the same as the voltage dropped across R3.
C) The voltage dropped across R2 added to the voltage dropped across R1 is equal to 12V.
D) All of the above are true statements.

Question 15

What is the total resistance of the circuit shown below?

A) 11 ohms
B) 21 ohms
C) 6 ohms
D) 12V x the total current

Question 16

Which is a correct statement with regard to the circuit shown below?

A) Electricity always takes the path of least resistance; therefore no current will flow through R1.
B) The same amount of electric current will flow through R1 and R2.
C) If R2 were removed from the circuit, the amount of current flow through R1 would remain unchanged.
D) The voltage dropped across R2 is much less than the voltage dropped across R1.

Question 17

Referring to the following circuit, which resistor has the highest voltage dropped across it?

A) R1
B) R2
C) Both R1 and R2 have the same voltage drop.
D) Neither resistor will have a voltage drop since no current will flow in this circuit.

Question 18

Which best describes the reason that a circuit breaker or fuse may interrupt electric current if someone is using too many household devices at the same time such as a hair dryer, microwave oven, and toaster?

A) The devices are all connected in series and each device that is switched on adds an additional series resistance.
B) The devices are all connected in parallel and each device that is switched on decreases the total circuit resistance causing the total circuit current to increase.
C) The circuit breaker or fuse has too small of a rating.
D) The electric company limits the amount of current supplied to a house.

Question 19

A technician measures 10A using a clamp-on inductive ammeter placed around the battery positive cable on a truck with the ignition on and engine off. He also measures 10A with the inductive ammeter placed around the battery negative cable. Which best explains the reason for these measurements?

A) Kirchhoff's voltage law
B) Ohm's law
C) Kirchhoff's current law
D) The rules of series-parallel circuits

Question 20

Which of the following is the largest value of resistance?

A) The total resistance of two 1k ohm resistors connected in series
B) The total resistance of two 1k ohm resistors connected in parallel
C) 1000 ohms
D) 100,000 milliohms