Topic 1 - Energy Flashcards
Name 8 energy stores
- Kinetic
- Thermal
- Electrostatic
- Gravitational Potential
- Elastic Potential
- Nuclear
- Chemical
- Magnetic
What are the four ways energy is transferred?
- Mehcanically - work done
- Electrically - work done by moving charges
- Heating
- Radiation
What is the law of conservation of energy?
Energy cannot be created or destroyed, only transferred between energy stores and objects
What is the net change of total energy in a closed system?
0
What 3 ways can energy be transferred?
- Heating
- Work Done
- Falling
How are gravitational potential energy and kinetic energy linked?
The are inversely proportional .e.g. energy lost from the gravitational potential energy store = energy gained in the kinetic energy store
What two things affect the amount of kinetic energy?
Mass and speed
What 3 things affect the amount of gravitational potential energy?
Mass, gravitational field strength and height
What two things affect the amount of elastic potential energy?
Spring constant and extension
What is specific heat capacity?
The amount of energy required to raise 1kg of a substance by 1 degree
In the specific heat capacity practical why do you put water around the thermometer?
It is a better thermal conductor than air, therefore making your measurements more accurate
What is another name for dissipated energy and why is it called this?
It is often called ‘waste energy’ as it is stored in a way which is not useful
What is another name for energy transferred?
Work done and energy transferred mean the same thing .e.g. P = WD/t or P = E/t
What is conduction?
The process where vibrating particles transfer energy to neighbouring particles, this is how energy can move through a solid substance
What common appliance relies on convection?
A radiator
How does lubrication reduce unwanted energy transfer?
Any moving object creates friction which transfers energy to thermal stores which are not useful
How does insulation reduce unwanted energy transfers?
Insulation is made up of materials with low thermal conductivity so that they can prevent energy from escaping
Why do we measure efficiency?
Having systems with higher efficiencies reduces costs and waste materials used to produce energy
