P1 - Energy Flashcards
4 energy transfer pathways
Mechanical
Electrical
Radiation
Heat
Specific heat capacity
The amount of energy needed to raise the temperature of 1kg of a substance by 1°c
Why does thermal insulation increase the efficiency of systems
It reduces unwanted energy transfer to the surroundings by reducing the rate of thermal conductivity
What is a thermal insulator
A material with a LOW thermal conductivity, reduces the rate of thermal energy transfers
Internal energy
Total energy in the kinetic and potential stores of all particles that make up a system
How can an objects internal energy be changed
Heating or cooling
Advantages of fossil fuel energy resources
Produces large amounts of electricity
Reliable
Short start up time
Law of conservation of energy
Energy cannot be created out destroyed only transferred from one store to another
Energy stores
Magnetic
Electrostatic
Nuclear
GPE
Elastic potential
Thermal
Chemical potential
Kinetic
System
Object or group of objects
When a system changes
Energy is transferred
Where can energy be transferred
- Into or away from a system
- Between objects
- Between energy stores
Closed systems
Systems where neither matter or energy can leave, net change in total energy is 0
How is energy transferred by heating
Thermal energy is transferred to the system
How is work done
- when a current flows against resistance in a circuit
- by force moving an object
