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New TopicCan you compare your answers to yesterday’s “energy circus” with answers from other groups. Who was
correct?!?
You have 5 minutes to do
this
Last lesson
• Types of energy
• Law of conservation of energy
• Energy flow diagrams
What is Energy?
“The capacity to do work”
Not a very good definition!
Types of energy
Energy can take many forms;
Light
Sound
Electric
Chemical
Gravitational potential
Nuclear
Types of Energy
Heat Chemical
Light Gravitational
Sound Elastic/strain
Kinetic Nuclear
Electric
Types of Energy
Heat Chemical
Light Gravitational
Sound Elastic/strain
Kinetic Nuclear
Electric
Stored/potential
The Law of Conservation of Energy
Energy can be changed (transformed) from one type to another, but it can never be made or destroyed.
This means that the total amount of energy in the Universe stays the same!
Energy Flow diagrams
We can write energy flow diagrams to show the energy changes that occur in a given situation.For example, when a car brakes, its kinetic energy is transformed into heat energy in the brakes.
Kinetic heat
Today’s lesson
Measuring the energy content of two fuelsYou will move to the next experiment at the appropriate signal.
Gather round Mr Porter
Energy Content of two fuelsFuel Initial
mass (g)
Final mass (g)
Mass of fuel used (g)
Initial temp of water (°C)
Final temp of water (°C)
Temp rise of water (°C)
Energy released (J)
Energy released per gram of fuel (J/g)
Wax
Ethanol
Volume of water (cm3) x 4.2 x temp rise
Energy ÷ mass
Then write three sentences saying what you have discovered, and suggesting two ways the experiment could be improved.
