what is energy
this is number in joules that determines what can happen
what are the 8 energy stores
- chemical
- thermal
- kinetic
- gravitational / gravity
- elastic
- nuclear
- electrostatic
- magnetic
what is an energy store
a store indicates how many joules of energy it can produce
how can energy be transferred
- mechanically (through force)
- electrically (with a current)
-heating by particles
heating by radiation
how can you work out the work done mechanically
work done (J) = force (N) X distance (m)
how can you work out the energy transferred electrically
energy transferred (J) = electrical power (W) X time (S)
what is the law of conservation of energy
energy cannot be created or destroyed it can only be transferred between stores.
what is a closed system
this is when no energy or particles are lost during a reaction
how do you analyse a situation using energy
- choose two points of a process
- Identify which stores have more or less energy in them at these points
- work out what type of energy transfer has occurred
how do you analyse a situation where a constant force is involved
you must take into account the physical actions of the object at the two points
and the stores of energy at the two points
