Sections 3 and 4. Law of Conservation of Energy Energy cannot be created or destroyed. It just...

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Sections 3 and 4

Law of Conservation of EnergyEnergy cannot be created or destroyed. It

just changes from one form to another.Some energy is given off as heat due to

frictionEx. Roller coaster – not all potential energy is

converted to kinetic as the car rolls downhill. Some is converted to thermal energy due to friction but it is not destroyed.

In every conversion, some energy is converted to thermal energy and given off as heat

Think about itYou drop a ball and it bounces. Which

bounce will be the highest – the first or the last and why?

That same ball slows down and eventually stops. Is the energy that was in the ball lost forever? Why or why not?

Energy ResourcesA natural resource that can be converted by

humans into other forms of energy in order to do useful work

Non-renewable resourcesCannot be replaced after they are used up in a

reasonable period of time.Nuclear energy is considered non-renewableFossil fuels are non-renewable resources that

come from the remains of plants and animals that died millions of years ago

Energy from fossil fuels originally came from the sun

When fossil fuels are burned, the energy from the sun is released

Examples of fossil fuelsCoalPetroleumNatural gas

All fossil fuels give off a large amount of pollution when burned. Those fuels get trapped in the atmosphere and can cause global warming

Converting Fuel into Energy

Renewable ResourcesCan be used and replaced in a relatively

short period of timeMany renewable resources do not pollute the

environment as much as fossil fuels and for the long term can be cheaper to run

Examples of renewable resourcesSolarWaterWindGeothermal (energy from within the earth)Biomass (dead stuff that is not millions of

years old) ex. Wood, corn etc

answer the following on a separate piece of paper

List 3 renewable resources and give a pro and con of each

List 3 non-renewable resources and give a pro and con of each

Do you think that there will be a shift to more renewable resources sometime within this century – why or why not

Why do you think we have not gone to mostly renewable resources yet?

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