8.1 - Magnetic Fields & Electromagnets

Question 1

What is Magnetism

Answer 1

• magnetism is a non-contact force cause by the arrangement of domains that make up the substance
• when the domains are lined up then the objects will be magnetic

Question 2

What do magnets have?

Answer 2

• all magnets have north and south poles
• like poles repel
• unlike poles attract

Question 3

Magnetic Fields

Answer 3

• the magnitude and direction of a magnetic field can be represented by field lines
• more lines per unit area = stronger magnetic field
• magnetic field lines outside magnet always flow north to south

Question 4

Magnetic fields associated with currents

Answer 4

• all electric currents produce a magnetic field
• the direction of the magnetic field can e found using the right hand grip rule

Question 5

Electromagnets

Answer 5

• Electromagnet (e.g solenoid) are magnets that can be turned on and off
• the strength of an electromagnet can be increases by adding an iron core or increase the number of coils