Transcript Electric Power

• Physics: pages 708-713
Direct vs. Alternating Current
 In direct current the current continually moves in
only one direction. Batteries use this type of
current to generate electric power.
 In alternating current, the charge carriers
continually change direction of movement (back
and forth) in opposite directions. Most devices
run off of this type to minimize loss of power,
since the charge carriers do not actually have
any displacement.
That’s all the
power she’s
got Captain!
What?
Watt?
Electric companies
measure energy
consumed in
kilowatt-hours
You are charged money per
kilowatt-hour used at your home.
6
3.6 x 10 J
Electric energy is
transferred at
high potential
differences to
minimize energy
loss
The power dissipated by a
resistor can be found with this
equation
2
P=I R
Homework:
P. 710 #1,2
P.712 #1,2
P. 713 #1-5