physics 1a
- Created by: lewis5151
- Created on: 23-05-17 13:42
View mindmap
- physics 1A
- heat transfer
- convection
- convection happens when the particles with the most energy move from the hotter place to the cooler place - and take the heat energy with them.
- conduction
- conduction of heat is where vibrating particles pass on their energy to the particles next to them
- infrared
- type of electromagnet radiation, as are radio waves, ultraviolet radiation, X-rays and microwaves.
- kinetic theory
- solids
- they dont have much energy so they can only vibrate
- liquids
- they have more energy then the particles in a solid - they move in all directions at low speeds
- gases
- they are free to move in any direction and move at high speeds
- solids
- the radiator example
- heating a room uses convection currents
- hot, less dense air by the radiator rises and denser, cooler air flows down to relce it.
- heating a room uses convection currents
- conduction and evaporation
- conduction
- is when a gas terns into a liquid E,G drinks glasses
- evaporation
- is when a liquid turns into a gas
- conduction
- convection
- energy and efficiency
- u-values
- shows how fast heat can transfer through a material
- heat transfers faster through materials with higher u-values
- cost effectiveness
- pay back = initial cost / annual savings (in years)
- specific heat capacity
- specific heat capacity is the amount of energy needed to raise the temp of 1kg of a substance by 1 oC
- O = TEMP CHANGE C = SPECIFIC HEAT CAPACITY M = MASS E = ENERGY TRANSFER E = M x C x O
- efficiency in machines
- efficiency = useful energy out / total energy in
- efficiency = useful power out / total power in
- 9 types of energy
- 1. electrical energy
- 2. light energy
- 3. sound energy
- 4. kinetic energy
- 5. nuclear energy
- 6. thermal energy
- 7. gravitational energy
- 8. elastic energy
- 9. chemical energy
- the cost of electricity
- energy transferred (j) = power (w) x time (s)
- u-values
- heat transfer
Comments
No comments have yet been made