energy transfer by appliances Flashcards
name some types of appliances at home
what do these appliances do?
transfer electrical energy into other forms of energies
blender kettle fan washing machine hair dryer iron etc
in exams we only need to identify transfers to what 2 energy types?
kinetic energy and thermal energy
describe the energy transfer between a blender and a fan
they are both powered by electrical energies and in both of these cases,
electrical energy is transferred into kinetic energy of electric motors because:
the main purpose in both of these appliances is movement
(blender moves to mix food)(fan moves to create air conditioning)
a small amount of thermal energy will also be generated due to the friction in the motors
the energy transfer of electrical energy to kinetic energy in electric motors causes another type of energy produced
what is this type of energy produced and how is it produced
small amount of thermal energy due to the friction in the motors
describe the energy transfers by appiance in an iron
and a kettle
both use electrical energy in the mains but they transfer thermal energy because
both of these appliances are designed to get hot
neither of these appliances generate kinetic energy, thats not what they’re designed to do
we can divide appliances into 2 main categories:
appliances that transfer ELECTRICAL ENERGY to thermal energy (kettle,iron etc)
appliances that transfer electrical energy to kinetic energy (blender,fan)
some appliances are applied to transfer electrical energy to both thermal energy and kinetic energy
what are 2 examples
a hairdryer
washing machine
electrical energy —> kinetic energy + thermal energy
both transfer electrical energy to both kinetic energy of electric motors and thermal energy
what does a motor do
what does the heating element do
moves air through the hairdryer and the heating element heats the air
what does a heating element and a motor do in the case of a washing machine?
heats the water
motor turns the drum to wash the clothes
all appliances have a power____
power RATING
what is power
the rate at which energy is transferred
what does a power of 1 Watt mean
1 Watt (W) is an energy transfer of 1J per second
a farm has a rating of 20WATTS
what does 20 watts mean?
it transfers 20 joules of electrical energy per second
a blender has a power rating of 400W what does this mean?
that the blender transfers 400 joules of electrical energy per second
appliances used to generate what type of energy, usually have a much higher power rater than appliances designed to generate ____ energy
appliances used to generate thermal energy, usually have a much higher power rater than appliances designed to generate kinetic energy
