energy Flashcards
what is an energy store
the different ways of which energy is stored in an object
what are the main types of energy stores
kinetic, magnetic, thermal, elastic potential, gravitational potential, chemical, nuclear
what is energy transfer
the process in which energy is moved from one store to another
what is the conservation of energy law
the fact that energy cannot be created nor destroyed
how can energy be transferred
mechanically, heating, electrically, radiation
what is a system
collection of matter/ objects
how does an open system effect energy transfer
- energy can be transferred with the outside world (any matter that is outside the system)
- open systems can loose or gain energy
how does a closed system effect energy transfer
- no matter or energy can enter or leave, energy is just transferred within the system
explain thermal energy and give the equation
energy due to heat
E = m × c × ΔT
Change in thermal energy = mass x specific heat capacity x change in temperature.
explain kinetic energy and give the equation
energy due to movement
Ek = 1/2 m v2.
half mass x velocity squared
explain gravitational potential and give the equation
Energy stored in an object due to its position in a gravitational field
Ep = mass x gravitational field x height
Ep = m x g x h
explain elastic potential energy and give the equation
energy stored in a stretched object
Ee = 1/2 x K x e squared
half spring constant x extension
what is power and give equation
rate of energy transferred
P = e/t
energy transferred divided by time
what is efficiency
how much of the energy transferred is useful energy in comparison to the energy wasted
what are the two types of energy recourses
non renewable and renewable
