SPH3U1
12.2 Oersted’s Discovery
Read 12.2 and 12.4
Compare magnetisms and electrostatics.
Magnets
Electrostatic charges
Positive and negative charges
opposites attract
like charges repel
many similarities…is there a relationship between the two?
Oersted discovered that when a current (I) is put through a copper wire
(which is not magnetic)
Oersted’s Principlea charge moving through a straight conductor
produces a
To determine the direction of conventional current or the magnetic field, use __________________.
___________
The thumb points in the direction of the conventional (positive) current.
The fingers curl in the direction of the magnetic field.
When looking at a cross-sectional area of the conductor, the magnetic field
lines are _________ (either clockwise or counter-clockwise). The current is
then pointing _______________________.
An ‘X’ is used to represent conventional current going into the page
A dot is used to represent conventional current coming out of the page
SPH3U1
12.4 Solenoids
Running a current through a single wire produces a
When the current flows in a circular pattern, what direction is the magnetic field?
A Solenoid is __________________________
Right Hand Rule for solenoids ________
Implications:
Electricity can be used to
The strength of the magnetic field can be increased by
increasing
increasing
changing the
Applications of Solenoids
Subwoofers
Electric Bells
In cars
Your Work: Read 12.2 and 12.4, Complete: p. 556 #1-3, 6,7 and p. 562 #1-4, 7