E N E R G Y
Energy is all around you! You can hear energy as sound. You can see energy in the light. And you can feel it as wind. Energy can be defined as the ability to do work. Because of the direct connection between energy and work, energy is measured in the same unit as work: joules (J).
Forms of Energy Chemical Electrical Sound Radiant / Light Mechanical Thermal/Heat Nuclear
Light Energy: Electrical Energy
Chemical Energy: stored in fuels & food Sound Energy
Mechanical Energy: an object in motion Thermal /Heat Energy Mechanical Energy: an object in motion
Nuclear Energy The sun’s energy is produced from a nuclear fusion Nuclear energy is the energy stored in the nucleus of an atom. Nuclear energy is unusual in that it can give off energy in the form of light or heat, but it is the change in the atom's makeup that produces the energy. The sun and power plants use nuclear energy. The sun’s energy is produced from a nuclear fusion
Is it possible to get mechanical energy from heat energy?
Energy can be changed from one form to another. Energy Conversions Energy can be changed from one form to another. At times we have a form of energy but it is not the one convenient for use. Therefore, we must convert it to another form. For example, Chemical heat
ACTIVITY Can you figure out the energy input and output in the following energy conversions?
Electrical mechanical Chemical heat + light
Energy changes in the production of electricity Mechanical energy in water Mechanical energy of turbine useful electrical energy + sound
The Law of Conservation of Energy Energy is neither created nor destroyed but only converted from one form to another. The total amount of energy in the universe is constant. Energy input = Useful energy output + wasted energy
ASSESSMENT SUMMARY