Download Electromagnets

Mrs. Brostrom
Integrated Science C
ELECTROMAGNETS
OBJECTIVE:

Describe the relationship between current and
magnetism.
WHAT IS MAGNETISM?
 Created
by moving electric charges (electrons)
 Has north and south poles
A
compass aligns with Earth’s magnetic field
 What happens when the compass is brought near an
electric current?
Needle is deflected (moved)
WHAT IS MAGNETISM?

In magnetic materials like Iron (Fe):
 Caused
by electrons moving around the nucleus
 Groups of atoms join together
 The magnetic field of each atom adds together to
create a larger magnetic field
ELECTROMAGNETS

Electricity and magnetism are related
 Electric
current in a wire creates a magnetic
field
 The stronger the electric current, the stronger
the magnetic field
ELECTROMAGNETS
A coil that has a soft iron core and that acts
as a magnet when an electric current is in
the coil is called an electromagnet.
 A coiled wire creates a greater magnetic field

 Each
loop increases the magnetic field
 Called a solenoid
 Safer than increasing electric current
ELECTROMAGNETS

One use of electromagnets is doorbells
ELECTROMAGNETS

Scrap-metal cranes also use electromagnets
ELECTROMAGNETS

Loudspeakers are also electromagnets
ELECTROMAGNETS

House telephones are also electromagnets
What type of energy transfer occurs with
electromagnets?
electromagnetic to electrical
LET’S TRY IT OUT
It’s time to build your own
electromagnet