Energy Flashcards
What is energy?
Energy is the ability to do work or cause change.
What are the three main ways of generating electricity?
- Fossil fuels (coal, oil)
- Nuclear power
- Renewable energy (sunlight, wind, water, solar panels, dams)
Compare conduction in solids, liquids and gases - which is the best?
Conduction occurs mainly in solids - most liquids are really poor conductors and hardly any conduction occurs in gases
Fill in the blank: Convection is the flow of heat energy from a region of ____ to a region of_____ by movement of a ______ or a ______ (these are called ______).
High temp
Low temp
liquid or gas
FLUIDS!!
What is radiation (heat transfer)?
The transfer of heat energy from an object by infrared waves.
It takes place without the need of any medium.
What is the primary purpose of insulation?
To reduce heat transfer.
Which fuel is renewable: coal, natural gas, or solar?
Solar.
What is conduction?
Conduction is a process where heat energy flows from a region of high temperature to a region of low temperature without overall movement of the material itself.
Vibrations pass from particle to particle, transferring heat energy as they do. Metals are good conductors of heat energy. Non-metals and gases are usually poor conductors.
What is a fluid?
Anything where particles can move – i.e. liquid or gas.
Which of the following is a non-renewable fuel: wind, oil, or hydroelectric?
Oil.
True or False: Insulators are materials that conduct heat well.
False.
What is the external source of energy for the Earth?
The Sun.
Fill in the blank: The process of heat transfer by radiation involves ______ waves.
infra red
(a type of electromagnetic wave).
What is conduction (describe what happens to the particles)?
Particles vibrating and transfering heat to neighboring particles.
Name a common insulating material.
Fibreglass. Polystyrene.
What type of energy generation uses wind turbines?
Renewable energy.
What is a fossil fuel?
A fuel formed from the remains of ancient organisms.
True or False: Convection currents can occur in both liquids and gases.
True.
What is the main advantage of using renewable energy sources?
They are sustainable and have a lower environmental impact.
Fill in the blank: The process where heat is transferred through a vacuum is called ______.
radiation.
What is biofuel?
Living (organic) material used as a renewable energy source.
e.g. farm manure used to produce biogas
e.g. wood
What does the term ‘energy efficiency’ refer to?
The useful energy output divided by the total energy input.
Which type of fossil fuel is considered cleaner: natural gas or coal?
Natural gas.
What is the primary method of heat transfer in metals?
Conduction.
Fill in the blank: The movement of warm air rising and cold air sinking is an example of ______.
convection.
What is geothermal energy?
Energy derived from the heat of the Earth.
True or False: Radiation can be felt as heat. (think heat lamps for geckos)
True.
What is the purpose of double glazing in windows?
To improve insulation.
Name one advantage of solar energy.
It is renewable and does not release greenhouse gases.
What is the difference between renewable and non-renewable energy sources?
Renewable sources can be replenished naturally (at a similar rate to the rate its being used), while non-renewable sources cannot.
Fill in the blank: Heat flows from areas of ______ temperature to areas of ______ temperature.
higher; lower.
What is the main disadvantage of using fossil fuels for planet earth?
They contribute to greenhouse gas emissions.
What is hydroelectric energy?
Energy generated from the movement of water.
True or False: Energy can be created or destroyed.
False.
Give an example of convection in the kitchen
Imagine water in a pan being heated. The water particles move faster and the fluid becomes less dense – and moves up to the top of the pan.
