Energy Conservation Flashcards
what does the law of conservation of energy state
energy cannot be created or destroyed only transferred
example of energy conservation
burning wood uses chemical energy in the wood to release thermal energy
list the 8 types of energy stores you need to know
kinetic thermal electrostatic chemical elastic potential gravitational potential magnetic nuclear
how is energy transferred
mechanically
what does the term “system” refer to
a single object or a group of objects
what happens when a system changes
energy is transferred
how can energy be transferred when a system changes
it can be transferred into or away from the system, between different objects in the system or between different types of energy stores
what is a closed system
a system where neither matter or energy can enter or leave
what is the net change in the total energy of a closed system
0
explain the transfer of energy in a boiling kettle of water
energy is transferred into the water from the kettle’s heating element by heating, into the water’s thermal energy store. this causes the the temperature of the water to rise
explain the change of stores when water is boiled by a kettle
energy is transferred electrically to the thermal energy store of the kettle’s heating element, which transfers energy by heating to the water’s thermal energy store
what is another way of saying energy transferred
work done
what are the 2 ways work can be done
when a current flows or by a force moving an object
explain the work done or energy transfer of someone throwing a ball in the air
the initial force exerted by the person to throw the ball does work. it causes an energy transfer from the chemical energy store of the persons arm to the kinetic energy store of the ball and arm
explain the work done or energy transfer of a ball being dropped
a ball dropped from a height is accelerated by gravity. the gravitational force does work. it causes energy to be transferred from the ball’s gravitational potential energy store to its kinetic energy store
