EXAM Stored energy In fuels Flashcards
Where do our bodies get energy from that we use to walk run and play.
From the food we eat.
When we burn a piece of wood, the stored energy is released in what two forms?
Heat and light.
To start a fuel burning, we often have to put in some energy to get the process burning e.g. We have to light a match to start a fire burning. What do we call this energy?
Input energy
Name 4 fuels that are commonly used for heating, lighting and cooking in homes in SA. Classify each as a solid, liquid or gaseous fuel.
Coal - solid fuel Natural gas - gaseous fuel Paraffin - liquid fuel Wood - solid fuel Candle wax - solid fuel
Explain the role of petrol in making a car move.
Petrol is the fuel that is burned in the car’s engine. This produces heat energy which allows the combustion gases to expand, drive the pistons and cause the engine to drive the car forward.
You are planning to have a braai for lunch and use charcoal briquettes as the fuel to cook your meat. Describe the input energy you will use to get the briquettes burning.
You will probably use a match to light some firefighters which is a fuel that burns very easily.
Explain what output energy is.
When fuels burn, the stored energy is changed into other forms of useful energy that are released as output energy.
What are the three things that make up the fire triangle?
Fuel, heat and oxygen.
Explain the process by which a candle is lit and burns.
A match is used to light the candle wick. The heat of the flame melts the wax which is drawn up the wick. The liquid wax then turns to gas and the gas is what is burned to keep the candle flame going.
How does a candle snuffer work?
The candle snuffer prevents oxygen from reaching the flame thus putting it out.
Use the fire triangle to explain how a firefighter thinks about putting out a fire.
Remove the fuel (e.g. Create a fire break)
Remove the oxygen by smothering the fire with a wet blanket
Remove the heat by putting water on a fire.
Give 3 example of renewable energy sources.
Solar, wind, tidal, wave
Give 3 example of non-renewable energy sources
Coal, gas, nuclear, oil
Explain what kinetic and potential energy is.
Kinetic is energy due to movement and potential energy is energy that is stored.
What action should you take if a fire breaks out in a building you are in.
Stay calm.
Stay low to the ground if there is smoke.
Leave through the closest exit.
Call the fire brigade.