Download Chapter 17-3 Electric Currents

• Michael Faraday
• A current can be produced by
pushing a magnet through a
coil of wire
• Causes a charges in wire to
move
• An electric current can be
produced in a circuit by a
changing magnetic field
• As wire moves in and out of
field – current will continue
• Rotating the current or
changing the strength of
magnetic field - Induces
current
• Pushing a loop through a
magnetic field requires work
• Greater the magnetic field –
stronger the force required to
push loop through field
• Electrical energy is produced
by electromagnetic induction
• Force at max value when
charged particles move
perpendicular to magnetic
field.
• Zero current when the wire
moves parallel to magnetic
field
• Convert mechanical energy to
electrical energy
• Loop of wire inside turns within
a magnetic field – current
produced
• For each ½ rotation of loop
• Current produced by generator
reverses direction
• Alternating Current (AC)
• Oscillating electric and
magnetic field
• Perpendicular to each other
• Perpendicular to wave
direction
Step-Up Transformer
• Increases voltage - output voltage
is greater than the input voltage
• # of wire turns on the secondary
coil > # of turns on the primary
coil
Step-Down Transformer
• Decreases the voltage - output
voltage is less than the input
voltage
• # of wire turns on the secondary
coil < # of turns on the primary
coil