Deck 12: Electric Current and Related Variables in Engineering

Question 1

The law that states that at any given time, the sum of the currents entering a node must equal the sum of the currents leaving the node is known as

A) Kirchoff's current law.
B) Kirchoff's voltage law.
C) Ohm's law.
D) Coulomb's law.

Answer 1

A

Question 2

Which subatomic particle has no charge?

A) Proton
B) Neutron
C) Electron
D) Ion

Answer 2

B

Question 3

If No. 26 wire has a diameter of approximately 0.016 centimeters, what is the diameter of No. 20 in centimeters?

A) 0.010 centimeters
B) 0.020 centimeters
C) 0.022 centimeters
D) 0.032 centimeters

Answer 3

D

Question 4

Which subatomic particle has a negative charge?

A) Proton
B) Neutron
C) Electron
D) Ion

Question 5

Which subatomic particle has a positive charge?

A) Proton
B) Neutron
C) Electron
D) Ion

Question 6

The flow of electric charge that periodically reverses direction that is typically produced by rotating generators is known as

A) ac current.
B) dc current.
C) $\text { ac/dc current. }$
D) omni directional current.

Question 7

The amount of work required to move charge between two points is represented by

A) electric current.
B) resistance.
C) voltage.
D) energy.

Question 8

Ohm's law describes the relationship between voltage, resistance, and current. Which of these is Ohm's law?

Question 9

In general, there are two ways in which the sun's energy is converted into electricity:

A) photovoltaic and photothermal.
B) photovoltaic and photochemical.
C) photovoltaic and photosynthetic.
D) none of the above

Question 10

Electric current is a fundamental dimension.

Question 11

Some materials exhibit near-zero resistance at very low temperatures. This behavior is called

A) infra-resistance.
B) anti-resistance.
C) semiconductivity.
D) superconductivity.

Question 12

Which of the following batteries is an example of a primary cell?

A) Nickel-cadmium (NiCd) also known as "nicad"
B) Nickel-metal hydride (NiMH)
C) Alkaline
D) Lead acid

Question 13

Voltage is sometime referred to as emf. What does emf stand for?

A) Electromagnetic frequency
B) Electromotive frequency
C) Electromagnetic force
D) Electromotive force

Question 14

Opposite charges repel each other and like charges attract each other.

Question 15

Primary cells are batteries that can be recharged while secondary cells are batteries that
cannot be recharged.

Question 16

The SI unit for electric current is

A) amperes.
B) electrons per second.
C) coulombs.
D) Watts

Question 17

The flow of electric charge that occurs in one direction that is typically produced by batteries is known as

Question 18

In all batteries, electricity is produced by

A) light.
B) heat.
C) a chemical reaction.
D) all of the above.

Question 19

A numbering system that describes the size of an electric conductor is AWG. What does AWG stand for?

A) American Wire Gage
B) Association of Wire Gages
C) Atlas of Wire Gages
D) All Wires are Good

Question 20

The electrical resistance of a material varies with temperature.

Question 21

Electrical components that store energy on two oppositely charged electrodes, rather than through a chemical reaction, are known as

A) batteries.
B) inductors.
C) transistors.
D) capacitors.

Question 22

In certain circuits, if one of the elements fails, that failure prevents the current from flowing through other elements in the circuit; thus the entire circuit fails. This type of circuit is a

A) parallel circuit.
B) series circuit.
C) none of the above

Question 23

When it comes to wire size, the larger the gage number, the larger the wire diameter.

Question 24

The ratio of how much light is produced by a lamp (in lumens) to how much energy is consumed by the lamp (in Watts) is known as

A) efficacy.
B) efficiency.
C) illumination cost.
D) energy cost.

Question 25

A common unit of illumination intensity is called a footcandle and is equal to

A) the amount of light one foot away from a candle.
B) the amount of light from a one-foot long candle.
C) one lumen distributed over an area of 1-square-foot.
D) none of the above

Question 26

Capacitors are used for

A) energy storage.
B) electronic filters.
C) timing elements.
D) all of the above

Question 27

Electrical resistance is a fundamental dimension.

Question 28

The distribution of light on a horizontal surface is known as

A) luminescence.
B) luminosity.
C) illuminescence.
D) illumination.

Question 29

In lighting design, a variable called CRI is often used. What does CRI stand for?

A) Crime Reenactment Investigation
B) Color Rendition Index
C) Capacitive-Resistive Index
D) none of the above