Chapter 3 Oral Questions

Question 1

One kilowatt is equal to how many watts?

Answer 1

1,000

Question 2

What law describes the basic relationships in an electrical circuit?

Answer 2

Ohm’s law

Question 3

What are the three elements of Ohm’s law?

Answer 3

Voltage, Current, Resistance

Question 4

How would you write Ohm’s law as an equation?

Answer 4

E= I X R, R=E/I, I=E/R

Question 5

If the resistance in a DC circuit remains the same but the voltage doubles, what happens to the amount of current flowing in the circuit?

Answer 5

It also doubles

Question 6

In DC circuits, what unit measures power?

Answer 6

Watts

Question 7

What three elements are required to form an electrical circuit?

Answer 7

A source of electrical energy, a load or resistance to use electricity, and wires or conductors to connect them (source, load, conductor)

Question 8

DC circuits can take one of three forms or types, what are they?

Answer 8

Series, Parallel, or Series-Parallel

Question 9

A 24 volt lead acid battery has how many cells?

Answer 9

12

Question 10

A fully charged lead acid battery has a specific gravity range between what two values?

Answer 10

1.275 and 1.300

Question 11

You must apply a correction to the specific gravity reading of the electrolyte of a lead acid battery when the temperature is outside of what two values?

Answer 11

when temp is less than 70 or more than 90 Fahrenheit

Question 12

What is the reason for having separate facilities for storing and servicing nickel-cadmium and lead-acid batteries?

Answer 12

The electrolytes are chemically opposite and the fumes from one can contaminate the electrolyte of the other

Question 13

The state of charge of a nickel-cadmium battery cannot be determined by measuring the specific gravity of the electrolyte for what reason?

Answer 13

There is no significant change in the specific gravity of the electrolyte as the battery is charged or discharged in Ni-Cad batteries

Question 14

What is the principal advantage of AC over DC?

Answer 14

Power can be transmitted over long distances more efficiently and with smaller wires because the voltage can be easily increased or decreased by a transformer

Question 15

What are the three causes of opposition to current flow in an AC circuit?

Answer 15

Resistance, Inductive reactance, and Capacitive reactance

Question 16

Define Inductance

Answer 16

An induced voltage which is opposite the direction of the applied voltage

Question 17

What component creates capacitance in AC circuits?

Answer 17

a Capacitor

Question 18

How does a capacitor store electricity?

Answer 18

Energy is stored in the form of an electrostatic charge or field that exists between two conductors separated by an insulator

Question 19

What property of an AC circuit is defined by the term impedance?

Answer 19

Total opposition to current flow

Question 20

What are two reasons that might cause a nickel-cadmium battery to fail to deliver its rated capacity?

Answer 20

Faulty cells or cell imbalance

Question 21

What electrical values are measured by a typical multimeter ?

Answer 21

Voltage, Current, Resistance

Question 22

What is the Ohm’s Law formula to find Power?

Volts?

Answer 22

Power: P = I x E

Volts: E = I x R