Lesson 5

Question 1

Resistance to the flow of electricity is measured in ? .

Select one:

a. amperes
b. ohms
c. volts
d. watts

Answer 1

b. ohms

Question 2

An electrical shock occurs when the ? becomes a part of the electric circuit.

Select one:

a. body
b. hand tools
c. live line tools
d. worker’s clothing

Answer 2

a. body

Question 3

It is important to understand three things about electricity in order to work with it safely: how parts of the human body react to it, how it can be directed, and how it ? .

Select one:

a. acts
b. builds current flow
c. creates heat
d. grounds itself

Answer 3

a. acts

Question 4

One of the factors that determine the resistance of a material is the ? of the substance.

Select one:

a. age
b. temperature
c. viscosity
d. weight

Answer 4

b. temperature

Question 5

The hand-to-hand resistance of a Qualified Electrical Worker working on a circuit is 5,000 ohms. The circuit voltage is 480 volts. The amount of current that would flow in the worker’s body if he becomes part of the circuit is ? .

Select one:

a. 66 mA
b. 86 mA
c. 96 mA
d. 106 mA

Answer 5

c. 96 mA

Question 6

One way for a person to receive an electrical shock normally occurs when he or she makes contact with one part of an energized circuit and the ground.

Select one:
True
False

Answer 6

True

Question 7

An outside electric current with as little as ? can upset the rhythmic, coordinated beating of the heart by disturbing the nerve impulses.

Select one:

a. 75 mA
b. 90 mA
c. 100 mA
d. 112 mA

Answer 7

a. 75 mA

Question 8

When it is dry, the outer layer of skin may have a resistance of several ? , but when it is moist, there is a radical drop in resistance.

Select one:

a. hundred ohms
b. thousand ohms
c. hundred thousand ohms
d. million ohms

Answer 8

b. thousand ohms

Question 9

The skin has a “breakdown” voltage at which point it is “punctured,” leaving only the lower resistance body tissue to impede the flow of current. This voltage will vary with the individual, but is in the area of ? .

Select one:

a. 120 V
b. 240 V
c. 600 V
d. 13,200 V

Answer 9

c. 600 V

Question 10

Electric shock can cause loss of ? , resulting in the inability to let go of an electrical conductor.

Select one:

a. brain function
b. heart function
c. lung/breathing function
d. muscular control

Answer 10

d. muscular control

Question 11

A severe shock can cause considerably more damage to the body than ? .

Select one:

a. a car accident
b. a fall from a pole
c. from a severe pinch point
d. is visible

Answer 11

d. is visible

Question 12

Head protection for workers exposed to electrical shock must be designed to provide protection against an accidental electrical contact.

Select one:
True
False

Answer 12

True

Question 13

The “let-go” threshold for a man receiving an electrical shock is between 9 and ? .

Select one:

a. 30 mA
b. 60 mA
c. 80 mA
d. 100 mA

Answer 13

a. 30 mA

Question 14

The possibility of cardiac arrest, severe burns, and death can occur when an electrical shock of ? occurs.

Select one:

a. 2,000 mA
b. 4,000 mA
c. 7,000 mA
d. 10,000 mA

Answer 14

d. 10,000 mA

Question 15

The ? part of an electrical arc is caused by the pressure developed by the near-instantaneous heating of the air surrounding the arc and from the expansion of the metal as it is vaporized.

Select one:

a. blast
b. incendiary
c. percussion
d. shock wave

Answer 15

a. blast

Question 16

Burning becomes the major effect on the body at ? .

Select one:

a. 480 V
b. 600 V
c. 1,000 V
d. 2,400 V

Answer 16

b. 600 V

Question 17

For arm and hand protection against electrical shocks, ? is considered the best material for insulating gloves and sleeves, and must conform to ANSI standards.

Select one:

a. cotton
b. kevlar
c. leather
d. rubber

Answer 17

d. rubber

Question 18

An arc generated at 480 volts can be just as dangerous as an arc generated at 13,800 volts.

Select one:
True
False

Answer 18

True