Download Fact Sheet: Mechanical Energy

Fact Sheet: Mechanical Energy
Everything in the universe is made up of matter.
Energy is what allows us to move or change
matter. Whenever energy is used to move or change things,work is done. Work can be done with
mechanical energy, which is energy possessed by an object because of its motion or the stored energy
of its position. When mechanical energy is moving, it is called kinetic energy.
Everything that is in motion has kinetic energy and has the ability to move or change other things.
When energy is stored in an object because of its position, it is called potential energy.
A stretched rubber band has potential energy and can spring into action when released.
A roller coaster at the top of the track has the potential to go roaring down the tracks at a high speed. As
an object’s kinetic energy increases, its potential energy decreases and viceversa.
A swing, at its highest point, has the greatest potential energy, while its kinetic energy is at its
lowest. As it moves to its lowest point, kinetic energy increases while potential energy decreases.
Energy is continually passing back and forth between these two states.
One of the most useful facts about energy is that it can also change from one form to another.
These changes are happening all the time. Sound is a form of mechanical energy that moves in waves
through matter.
Most machines transfer energy from one form into another in order to do work.
At a wind farm, the blades of a windmill are moved by the mechanical energy of the wind and
generate electrical energy. Chemical energy from the food we eat is transferred to mechanical energy
for action. Similarly, the chemical energy in gasoline is converted to mechanical energy to
operate vehicles and tools. Simple machines, such as the lever and the inclined plane, help make work
easier .
Work — To move or change something. Doing work takes energy.
Energy — The ability to make things happen or to do work.
Forms of energy - potential, kinetic, thermal, electrical, chemical, nuclear
Potential energy - Energy that is stored , no movement
Kinetic energy — Energy an object has when it is moving
Mechanical energy —The combined energy of an object due to its motion and position
Review Questions
1. Everything in the universe is made up of what ?
2. When energy is moving, what is it called ?
3. Everything that has motion, has kinetic energy … true or false
4. Stored energy is called what ?
5. Give an example of potential energy .
6. Sound is a form of what kind of energy ?
7. Define work.
8. Blades of a windmill are moved by what kind of energy ?
9. Chemical energy in gasoline is converted to what type of energy ?
10. Levers, & inclined planes are known as what type of machines ?