Paper 1 - Energy Resources and Energy Transfers Flashcards
What is the equation for Power?
P = W / t
What are the 8 energy stores?
- chemical
- kinetic
- gravitational
- elastic
- thermal
- magnetic
- electrostatic
- nuclear
What are the 4 energy transfers?
- mechanically
- electrically
- by heating
- by radiation (light and sound)
What is the equation for Work Done?
W = F x d
What is the equation for kinetic energy?
KE = 1/2 m x v^2
What is the principle of conservation of energy?
Energy cannot be created or destroyed it can only be transferred
What is the equation for energy efficiency?
efficiency = (useful energy output / total energy input) x 100
How could thermal energy transfer take place by conduction due to certain characteristics of an object?
- Thermal energy is transferred from one object to another because metal is a good conductor of heat
- Thermal energy is transferred from an object to the air particles because black is a good emitter of hear
How could thermal energy transfer take place by convection?
- Thermal energy is transferred to air
- Hot air is taken up by a fan in a convection current and exits the container to cool down
How could thermal energy transfer take place by radiation?
- Electromagnetic energy transfers heat
- A heat source will use electromagnetic waves to transfer energy to the surroundings
Explain the role of convection in everyday phenomena
- Heating a of of water in an example
- Bottom the pan heats up because energy is transferred from the heat source to the pot via conduction
- Kinetic energy is transferred to the water molecules at the bottom of the pan which heat up and the rise
- So other water molecules gain kinetic energy
- Creates a convection current
Explain how emission and absorption of radiation are related to surface and
temperature
- The colour black is very good at emitting and absorbing heat
- Metal is very good at emitting and absorbing heat
Explain ways of reducing unwanted energy transfer
- Insulation to prevent energy from being lost as heat to the surroundings
- Use thicker materials
- Use materials with low thermal conductivity
What is work done equal to?
Energy transferred
What is the equation for gravitational potential energy?
GPE = m x g h