Part 0 Flashcards
what is the equation for work done?
force x distance moved
what is work done measure in?
joules
what do work done and energy transferred have in common?
they are equal
describe the energy transfer of wind to electricity
kinetic energy from the wind turns a turbine which turns a generator which produces electricity
describe the energy transfer of water to electricity
kinetic energy from water turns a turbine which turns a generator which produces electricity
describe the energy transfer of geothermal resources to electricity
thermal energy heats water, water turns into steam, the thermal energy of the steam then turns a turbine which then has kinetic energy, the turbine turns a generator which produces electricity
describe the energy transfer of solar heating systems to electricity
thermal energy from the sun heats water which turns into steam that turns a turbine that then has kinetic energy, the turbine turns a generator which produces electricity
describe the energy transfer of solar cells to electricity
light energy from the sun is transferred into electrical energy
describe the energy transfer of fossil fuels to electricity
chemical energy is burnt to form heat energy as it causes water to evaporate, the kinetic energy of the steam is used to make a turbine spin which is connected to a generator transferring it to electricity
describe the energy transfer of nuclear power to electricity
chemical energy is burnt to heat water which turns to kinetic energy that turns a turbine connected to a generator which produces electricity
how is energy transferred by conduction?
when heat is applied to a solid the particles begin to vibrate. These particles vibrate faster and faster throughout the entire material causing it to heat up
how is heat transferred by convection?
in liquids and gases when heat is applied the particles gain energy (thermal-kinetic) and move faster. They move further apart and become less dense causing heat particles to rise. Eventually they cool again and sink until they become closer and more dense again; this process continues creating a convection current
how is energy transferred by radiation?
this is when heat is transferred through infrared waves. The hotter the object, the more infrared radiation it emits. This does not need matter to occur. It is a type of EM radiation and can happen even in a vacuum, unlike convection and conduction
what are bad conductors of heat called?
insulators
how do insulators reduce energy transfer from buildings?
heat loss through windows is reduced using double glazing with air or a vacuum between the two panes of glass as air is a poor conductor of heat and a vacuum can only transfer heat by radiation. Heat loss through walls and roofs is reduced using loft/wall insulation as it stops heat loss by conduction and convection preventing air from circulating inside
