physcics 1 Flashcards
(19 cards)
Energy
measured in joules or kilojoules
Energy stores (8 stores)
thermal kinetic elastic gravitational chemical, magnetic nuclear and electrostatic
what are the different Energy pathways (5)
mechanical heat electrical light and sound
conservation of energy
Energy cannot be created or destroyed it is transferred between stores
what is fuel as a material
material that contains a store or chemical energy
useful energy
Energy that has been transferred into the required form. e.g. a combustion engine transfers the chemical energy stores in a fuel into the kinetic store of the moving parts of the engine
wasted energy
Energy transferred into a form that is not required, e.g. a TV transfer some electricity into the thermal energy
how do you calculate energy efficiency?
The proportion of energy usefully transferred.
calculated by useful energy output divided by total input energy
Sankey diagram
Shanky diagram shows the proportion of energy transferred into a useful and wasted energy
temperature
Measure of how hot or cold is something is
heat used as what
An energy path
Infrared radiation
an electromagnetic wave (light ray) that transfers the thermal energy
Absorb
To take in
Emit
to give out
convection
heat transfers through fluids (liquid, and gases). As particles gain the energy, they become less dense and float. As they cool down the sink.
thermal radiation
Thermal radiation is the emission of electromagnetic waves (infrared light rays) from all hot objects.
thermal energy is the kinetic energy of random movements of atom and molecules in matter
work done
measured in joules or Newton meters 1J = 1Nm
it is a measure of the energy transferred to or from an object which allows it to be moved.
Work done ( J or Nm) = force (N) X Distance (m)
conduction
heat transferred through solids . Vibrating particles pass on energy to the next particle
conduction
heat transfer through soldis. vibrating particles pass on energy to the next particle
