ENERGY Flashcards
What are the different types of energy stores?
Thermal
Kinetic
Gravitational potential
Elastic potential
Chemical
Magnetic
Electrostatic
Nuclear
How can energy be transferred?
By heating
By work done
What is an example of work done?
A person throws a ball
Energy transferred from the chemical energy store in the person’s arm to the kinetic energy store of the ball and arm
What happens when an object speeds up or slows down?
Energy is transferred to the kinetic energy store when an object speeds up and vice versa
What is a system?
An object or group of objects
How can energy be transferred?
Mechanically (force doing work)
Electrically (work done by moving charges)
Heating
What happens the higher an object is lifted?
The more energy is transferred to the gravitational potential energy store
What happens when an object falls?
Energy is transferred from its gravitational potential energy store to its kinetic energy store
What happens when there is air resistance on a falling object?
It causes energy to be transferred to other energy stores such as the thermal energy store
What is specific heat capacity?
The amount of energy needed to be transferred to a substances thermal energy store to increase its temperature by 1 degrees
What is the conservation of energy principle?
Energy can be transferred, stored or dissipated but can never be created or destoryed
Why is not all of the energy transferred useful?
There is wasted energy when the energy is being stored in a way that is not useful (e.g. thermal energy)
What is power?
The rate of energy transfer/doing work
What is conduction?
The process where vibrating particles transfer energy to neighbouring particles (shared across kinetic energy stores which vibrate the particles faster so they collide causing energy to be transferred)
What is thermal conductivity?
How quickly energy is transferred by conduction (to the thermal energy store across the kinetic energy store)
What is convection?
When energetic particles move away from hotter to cooler regions (only occurs in liquids and gases)
What are convection currents?
Warm air rises
Cool air sinks to replace rising air