3.2 - Energy Transformations Involving Electrical and Mechanical Energy

Question 1

What are the parts of a motor?

Answer 1

• Armature or rotor (electromagnet)
• Commutator
• Brushes
• Axle
• Field Magnet
• Power Supply

Question 2

How does the motor work?

Answer 2

• A motor uses magnets to create motion
• The poles of the magnets attract and repel
• The north end of one magnet will repel the north end of the other (and similarly, south will repel south)
• Inside an electric motor, these attracting and repelling forces create rotational motion

Question 3

What are the 2 types of magnets in the motor?

Answer 3

• The armature (rotor) is an electromagnet

- The field magnet is a permanent magnet

Question 4

What is the St. Louis Motor?

Answer 4

• Used to demonstrate the functioning of the electric motor
• The poles of the electromagnet are reversed as the current travels the opposite way on the armature
• As the poles are reversed the armature is constantly attracted/repelled by the permanent magnets

Question 5

What is Alternating Current?`

Answer 5

• Aka AC.
• Called AC because it flows back and forth 60 times/second
• Commonly used in household circuits

Question 6

What is Direct Current?

Answer 6

• Aka DC
• Called DC because the current flows in one direction
• Commonly used in mp3s, cell phones and calculators