p1 Flashcards
(23 cards)
what is energy measure in
joules
what stores of energy are there
kinetic
gravitational potential
elastic potential
thermal
what’s kinetic energy
the faster an object goes the higher the kinetic energy is
what’s GPE
the higher off the ground an object is, the more GPE it has
more GPE it has to lose if it falls to the ground
what’s specific heat capacity
how much energy is needed to raise the temperature of 1kg of a substance by 1 degree celsius
what happens if you increase the temperature of particles
they move faster - have more kinetic energy
what’s the specific heat capacity practical
measure mass of metal block or water in beaker using balance
Place electrical heater in metal block/water
Measure initial temperature of substance using thermometer
Turn heater on, start time and measure potential difference and current supplied to heater using voltmeter and ammeter
After set time, measure final temperature and calculate change in temperature (final temp - initial temp)
As energy is lost to surroundings temp change will be less so specific heat capacity will be higher
what is power
the rate of energy transfer
what’s the unit for power
watt
formula for power
energy transferred / time
formula for efficiency
useful efficiency or power out / total efficiency or power in
(x100 to give percentage)
how is thermal energy lost
through conduction by transferred energy to outside surroundings
what’s an energy source
where we harness energy from in the world
is an energy source a store
no
is a finite source replaceable or not
not
is a renewable source replaceable or not
replaceable
what’s a fossil fuel
a source burned to produce heat or power
what’s an example of a fossil fuel
coal
oil
natural gas
what’s nuclear fuel
used in nuclear reactors to produce heat
what’s wind power
wind has kinetic energy used to turn turbines
what’s hydro electric
water behind dam has GPE, falls through turbine
what’s solar power
light from sun produces electricity
what’s biofuel
plant matter burned to produce heat
