Energy, Forms of Energy, Conservation of Energy

1. Energy
Motasem Abushanap
Defining Energy, its forms and Laws
11/2/2012

2. Energy
What is Energy?
Energy is the ability to do work, and it is a scalar physical quantity.
Energy can be transformed into another sort of energy. But it cannot be
created AND it cannot be destroyed. Energy has always existed in one form
or another.
What is The Energy Measuring Unit?
The measuring unit of Energy is "joule" which named after an English
scientist James Prescott Joule who lived from 1818 to 1889. He discovered
that heat is a type of energy.
Energy Forms:
1- Chemical energy.
2- Electrical energy.
3- Heat (thermal energy).
4- Light (radiant energy).
5- Mechanical energy.
6- Nuclear energy.
Types of Energy
Energy can be classified in two types:
1- Potential Energy (Stored Energy).
2- Kinetic Energy (Moving Energy).
Conservation of Energy Equations:
Energy cannot be created or destroyed, but it can be converted
(transformed) from one form to another. For the idealized roller coaster, all
energy is conserved through conservative forces, such as gravity. As the
train accelerates down the lift hill, potential energy is converted into kinetic
energy. When the train ascends another hill, the kinetic energy is converted

3. into potential energy again. This is conservation of mechanical energy, and it
continues throughout the entire ride. The total mechanical energy for the
train is shown by the equation:
E=K.E+P.E…………………………………………………………………1
P.E=m.g.h…………………………………..…………………...…………2
K.E=1/2(m.v2)……………………………………………..…..…………..3
By applying conservation of energy, and imagining that we have an
initial state and final state the equation became:
Ei = Ef................................................................................................4
K.Ei + P.Ei=K.Ef + P.Ef....................................................................5
Where:
E= Total Energy (Joule).
P.E= Potential Energy (Joule).
K.E=Kinetic Energy (Joule).
m= Mass of the body or system (Kg).
g= gravity acceleration (m/s2).
h= height of the system (m).
How do we Use Energy?
1- Energy is Light
Light is one type of energy that we can have by converting electricity
or chemical energy to light.
2- Energy is Heat
Heat is another type of energy that we can have by converting
electricity of chemical energy into heat, it is called also Thermal Energy and
it has three Law, Called Thermodynamics Laws..

4. 3- Energy Makes Things Grow and Move
Plants uses chemical energy and light to grow, fish in the sea converts
chemical energy into kinetic energy so it can moves, Humans convert
chemical energy inside the food so they can grow and move.
4- Energy Runs Machines
Inside the machine there is a device called electrical motor, whose job
is to convert electricity into mechanical energy so the machine can run, or in
an opposite way, a device called generator is responsible to convert
mechanical energy into electricity.
5- Energy Doesn’t Disappear
From the conservation of energy law, the amount of energy available in
world is a fixed amount that cannot be changed, neither by destroying it nor
creating it, but it available in many forms that it can change it form from one
to other.
References
1- The NEED Project P.O. Box 10101, Manassas, VA 20108 1.800.875.5029 www.NEED.org
2- http://www.energyquest.ca.gov/story/chapter01.html
3- http://ffden-2.phys.uaf.edu/211_fall2002.web.dir/shawna_sastamoinen/Conservation.htm
4- http://en.wikipedia.org/wiki/Conservation_of_energy