Download Lesson 2 - Electromagnetism

ELECTROMAGNETISM
Text book Pages 167 and 168
Magnetic materials
Which of the materials below are magnetic?
wood
wood
Question 2: Fill in the N and S pole.
N
S
Remember the trick: Just like
Canadians in the winter,
magnetic field lines like to go
away from the North and towards
the South.
Question 3: Fill in the N and S poles
Question 4: Add the field lines around
each magnet.
BIG question for today:
How can electricity
create a magnetic
field?
Electricity and Magnetism
 Current Intensity:
The rate of electron
flow: C/s
 This flow of electrons
can generate a magnetic
field.
Straight line conductors
 When electricity flows through a wire (straight line conductor) an
magnetic field is generated.
 The direction of this magnetic field can be seen using a compass. The
compass will point in the direction of the magnetic field.
What if I don’t have a compass?
Right Hand Rule
CONVENTIONAL
CURRENT!
USE CONVENTIONAL CURRENT!
What if I don’t have a compass?
Right Hand Rule
But... What if I don’t have a compass?
 There’s a trick! Grab your popsicle sticks.
 In our analogy, the popsicle stick is the wire.
Write + and – on the ends of your stick.
2) Grasp the stick with your RIGHT HAND and with your
thumb pointing in the direction of CONVENTIONAL
CURRENT FLOW. (+ to -)
3) Your fingers indicate the direction of the magnetic field.
1)
Determine the direction of the magnetic field.
**Use the direction of the CONVENTIONAL
CURRENT! (e- flow from + to -)