Electrical Principles Module Questions

Question 1

What is the smallest part into which you can divide matter without changing its makeup?

Answer 1

A molecule

Question 2

Of what are molecules made?

Answer 2

Atoms

Question 3

What are the 3 basic components of an atom and their electrical charges?

Answer 3

• neutrons (no charge)
  neut = neutral
  -protons (positive)
  pros are positive
  -electrons (negative)

Question 4

What is a stationary electric charge called?

Answer 4

Static electricity

Question 5

What is a moving electric charge called?

Answer 5

Electric Current

Question 6

Like charges _________ each other

Answer 6

repel

Question 7

Unlike charges ________
each other

Answer 7

attract

Question 8

What is magnetic flux?

Answer 8

The entire magnetic field surrounding a magnet

Question 9

What are the 3 principles of electromagnetism?

Answer 9

1. Moving electrically charged particles create magnetic fields

2.Magnetic fields attract or repel moving charged particles

3. Moving magnetic fields near charged particles causes current flow

Question 10

Higher currents in a conductor cause _________
magnetic fields around the conductor.

Answer 10

Stronger

Question 11

When a voltage is generated by a magnetic field moving through a conductor, that voltage is known as _______________. The current caused to flow is called ________ current

Answer 11

1. Electromotive Force EMF
2. Induced

Question 12

Why does inserting a soft iron core into a solenoid winding greatly strengthen the power of the magnet created?

Answer 12

Iron has higher permeability than air creating a stronger electromagnet

Question 13

An electromagnet ________
most of its magnetism when it is de-energized.

Answer 13

Loses

Question 14

4 uses of electromagnetic devices are;

Answer 14

Solenoid Valves
Electric Motors
Scrap Yard Crane Magnets
Electric Brakes

Question 15

Describe a conductors reaction to current flow?

Answer 15

Conductor exhibits little resistance to flow to the electric current.

Question 16

Name 3 good conductors;

Answer 16

Gold, Silver, Copper

Question 17

Describe an insulators reaction to current flow.

Answer 17

Insulator offers high resistance to flow of electric current

Question 18

Name 3 good insulators

Answer 18

Glass, Mica, Plastics, Ceramic

Question 19

A semi-conductor is a material that is neither a good ___________ nor a good ___________.

Answer 19

Insulator
Conductor

Question 20

Name 2 of the most common semi-conductor materials

Answer 20

Silicon
Germanium

Question 21

What does direct current mean?

Answer 21

Direct Current (DC) always flows in same direction.

Question 22

Name 2 sources of direct current

Answer 22

DC Generators
Batteries

Question 23

Name 4 uses of Direct Current

Answer 23

Electronics
DC Motors
Electromagnets
Welding

Question 24

What does alternating current mean?

Answer 24

Alternating current changes directions regularly and continuously

Question 25

What is the alternating current wave called?

Answer 25

Sine Wave

Question 26

Frequency is the measure of the ______________________

Answer 26

of cycles generated per second

Question 27

When referring to electrical loads, a phase is an instant in time on a sine wave and is measured in
__________ of ________.

Answer 27

degrees of rotation

Question 28

Name 2 sources of alternating current

Answer 28

Inverter
AC Generator

Question 29

Voltage can be compared to ____________ in a hydraulic circuit

Answer 29

Pressure

Question 30

Amperage can be compared to _______________ in a hydraulic circuit

Answer 30

rate of flow

Question 31

An ampere is a measure of?

Answer 31

current flow

Question 32

Define Open Circuit

Answer 32

an imcomplete path for current flow