Transcript Document

Energy Notes
ENERGY - the ability to do work or cause change
** You can think of work as the transfer of energy
** The two general kinds of energy: Kinetic Energy and Potential Energy
**Every chemical reaction involves a change of energy. Some reactions release energy and
others absorb energy.
KINETIC ENERGY - the energy of motion
**Kinetic Energy of an object depends on both mass and velocity.
**Kinetic energy increases as mass increases. Kinetic energy increases when
velocity increases.
Kinetic Energy = (Mass x Velocity2) / 2
POTENTIAL ENERGY - energy that is stored and held in readiness (potential to do work)
Mechanical Energy - the energy associated with the motion or position of an object. This
type can occur as kinetic or potential.
Thermal Energy - the total energy of the particles in a substance or material. When the
thermal energy of an object increases, its particles move faster, making the temperature of
the object rise. These particles have both potential energy and kinetic energy.
Chemical Energy - potential energy stored in CHEMICAL BONDS that hold chemical
compounds together.
Electrical Energy - the energy carried by MOVING ELECTRICAL CHARGES that produce
electricity
Electromagnetic Energy - Energy that travels in waves. These waves have some
electrical properties and some have magnetic properties. The light you see each day is an
example.
Nuclear Energy - potential energy stored in the nucleus of an atom and is released during
nuclear reactions. Nuclear fission happens in Nuclear power plants. Nuclear fusion happens
in the sun and other stars.
CALORIE - a unit of heat energy - the amount of heat required to raise the temperature of 1 g
of pure water by 1º Celsius
LAW OF CONSERVATION OF ENERGY - when one form of
energy is converted to another, no energy is destroyed. Energy
cannot be created or destroyed.
**In every physical change or chemical change, the total amount of energy stays
the same.
TEMPERATURE - a measure of the average kinetic energy of
the individual particles in an object.
HEAT - The movement of THERMAL ENERGY from a
substance at a higher temperature to another at a lower
temperature
**
Heat can move in 3 different ways
CONDUCTION - heat is transferred from one particle of matter to another
WITHOUT the movement of matter itself.
CONVECTION - heat is transferred by the MOVEMENT of
currents within a fluid (a liquid or a gas).
RADIATION - the transfer of energy by electromagnetic waves. Radiation
does NOT require matter to transfer thermal energy.
**A material that conducts heat well is called a conductor.
**A material that does NOT conduct heat well is called a insulator.