Power Flashcards
what are some applications of series circuits?
christmas lights, alarms
is a household powered by a series and or parallel circuit? why?
PARALLEL, voltage is the same so more power supplied to each light switch
what is direct current?
current only flows in one direction
what is alternating current?
current changes direction periodically
one cycle is how many hertz?
50 hertz
is the resistance of the skin high? what can it be lowered by?
yes
water
it is not the voltage that causes harm, it is the ____
current
what is power?
rate at which energy is transformed from one form to another
what are the units for power?
watts, Js-1
what does a power rating for an appliance do?
tells user how much power the device uses.
if a device gets warm when its not supposed to get warm, the energy wasted is in the form of ___
heat
if a device is heard when its not supposed to make sound, the energy wasted is in the form of ___
sound
efficiency of a device (power)?
how well a device changes energy from one form to another
all devices waste, no device is 100% efficient
true/false
true
what is the unit for measuring the power of an applicance
kWh
kilowatt hour
how is a kilowatt hour calculated?
kilowatts* hours
power*time
in an electric system, what is the order of distribution, transmission and generation?
generation, transmission, distribution
