General
Hydroelectric and Solar energy
Biofuels and geothermal energy
Wind energy
Fossil fuels
100
What is the SI unit for energy? (Symbol and word)
A joule, J
100
What is hydroelectric energy? (Definition)
Hydroelectric power stations store water in a reservoir behind a dam, the water flow turns the blades of a wind turbine which generates energy
100
What are the uses of geothermal energy?
The steam can be used to heat homes and generate electricity.
100
What is the energy conversion?
Kinetic energy-> electrical energy
100
Are fossil fuels renewable or not?
They are not
200
For one J of energy how much work van be done?
One J of work
200
Give the definition and uses of Solar energy.
The energy in sunlight can be converted into electrical by photovoltaic or solar cells Uses- heating water Steam can make a turbine spin to generate energy
200
What is the definition and energy conversion of geothermal energy?
Geothermal energy derived from hot rocks deep underground in volcanic areas. Heat-> Kinetic energy -> electrical energy
200
What are the uses of wind energy?
Gives electricity to houses and research stations mainly in remote area's.
200
What is the definition of fossil fuels?
Fossil fuels are made from dead plants and animals.
300
What 2 things need to happen for work to be done on an object?
Force has to act The force must move the same direction as the object
300
What are the impacts on the environment? (Both)
Hydroelectric- No pollution could cause floods Solar- No harmful things :)
300
What is the energy conversion of biofuels and is biofuels renewable or non-renewable?
Chemical potential energy-> heat-> kinetic energy Non-renewable
300
Give the definition of wind energy.
An energy source that converts the energy from wind into energy that rotate wind turbines to make electrical energy.
300
Name the 2 energy conversions ( burning and in vehicles)
Burning- chemical potential energy -> heat -> kinetic energy -> electrical energy Vehicles- chemical potential energy-> heat -> kinetic energy
400
There are 2 main energy sources- name them
Non-renewable (they are limited) and renewable (they aren't)
400
What are the uses of hydroelectric energy? Which is better, why?
Hydroelectric power stations supply electrical energy to houses and factories ( just like Eskom ;) Solar energy is better because there are no bad impacts on the environment.
400
Give the definition and uses of biofuels.
Biofuels derived from animal and plant matter like hyacinth and sugarcane. It can ne turned into biodiesel fuel for vehicles.
400
Through what medium does infrasound travel and how fast?
Air and 330 m/second
400
What are fossil fuels used for?
Petrol, diesel, kerosene ( burnt in jets), fuels for cooking and electricity.
500
Energy can't be .... Or .... Only ....
Energy can't be created or destroyed only converted. (Go learn what energy, I'm only putting it in ;) )
500
What are the energy conversions of both energy's?
Solar- Light energy -> Electrical energy Hydroelectric- Gravitational potential energy -> kinetic Energy -> Electrical energy
500
What is the impact on the environment? (both)
Biofuels- when biofuels are burnt carbon dioxide is made, if the plants grow as quickly as they are burnt it will affect global warming. Geothermal- the power stations extract poison (like hydrogen sulfide or arsenic) from under ground, the land around may sink causing damage and the flow of rainfall can be affected.
500
What is the impact of the environment is it good or bad?
Bad, the wind blades can kill birds and bats. They produce a low frequency sound- infrasound which makes people feel nauseous.
500
What is the impact on the environment
The carbon dioxide that fossil fuels make causes Global warming.
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