6th grade ch 3 sec 3 electricity from magnetism
TRANSCRIPT
Ch. 3 Sec. 3Electricity from
Magnetism
(Electromagnetic) induction
• Process of generating an electric current by moving a conductor in a magnetic field
• Produces induced current
The flow of an induced current may be constant, or
may change direction.
http://www.youtube.com/watch?v=gfJG4M4wi1o
DC• Direct Current• Charges flow in
1 direction• Used by
Thomas Edison• Type of current
found in battery
AC• Alternating Current• Charges move back & forth
in circuit• Used by Nikola Tesla• Advantage over DC-voltage
can be easily raised or lowered
• Type of current found in homes
Bill Nye The Science Guy- AC/DC Charge
• Well, everybody knowsThat when electrons flowThat flow is known as electricityAnd although you might say "So?", without it don't you knowYou'd be unplugged but not on MTVNow in a battery, current's called DCIt flows straight from the minus to the plusBut the current in your wall is known as AC, y'allAnd it cycles back and forth without a fuss.
So don't lose that charge, that AC/DC chargeYour current alternating or direct'Cause if you lose that charge, that AC/DC chargeThere's no reason for a circuit to connectOooooooh
YouTube video-Bill Nye AC DC song
http://www.youtube.com/watch?v=JZjMuIHoBeg&feature=related
http://www.youtube.com/watch?v=g17f9J1-r-k
http://www.youtube.com/watch?v=8VEg6L2QG5o&feature=related
Direct and Alternating Current
Electric generator Electric motorMechanical energy electrical energy
Electrical energy mechanical energy
DC AC
AC vs DC
TRANSFORMER• device that increases
or decreases voltage
• consists of 2 separate coils of wire wrapped around an iron core
1. primary coil2. secondary coil
primary coil
• connected to a circuit w/ a voltage source & alternating current
secondary coil
• connected to a separate circuit that does not contain a voltage source
http://www.youtube.com/watch?v=VucsoEhB0NA&feature=related
Electric current from generating plant
• AC• transmitted
@ high voltage used @ low voltage
STEP-UP TRANSFORMER
• increases voltage
STEP-DOWN TRANSFORMER
• decreases voltage
Schoolhouse Rock-Electricity