This document discusses different types of energy. It defines energy as the ability to do work and identifies the joule as the standard unit of energy. There are two main types of energy: kinetic energy, which is the energy of motion, and potential energy, which is stored energy due to an object's position or configuration. Kinetic energy is calculated as one-half the mass times the velocity squared, while potential energy is calculated as the mass times the gravitational field strength times height. Examples of kinetic energy include a moving car and flowing river, while potential energy examples include water stored behind a dam and a book on a table.

3. Sources of energy
• Sun
• Food

4. Energy
• Energy is the ability to do work
• Different forms of energy are mechanical
energy , heat energy , light energy , etc

5. Unit of energy
• The unit of energy is JOULE.

6. Different types of Energy
• Energy are of two types
• 1: Kinetic energy
• 2: Potential energy

7. KINETIC ENERGY
• The kinetic energy of an object is the energy
which it possesses due to its motion.
• It is defined as the work needed to accelerate
a body of a given mass from rest to its
stated velocity..

8. Equation of kinetic energy
• The kinetic energy of a point object or a non-rotating
rigid body depends on the mass of the
body as well as its speed.
• The kinetic energy is equal to the mass
multiplied by the square of the speed,
multiplied by the constant ½. In formula form:
KE=½ mv2

9. Examples of Kinetic Energy
A moving car

10. River flowing

11. A moving body

12. Example of kinetic energy
• 1. Moving car
2. Moving ball
3. River flowing
• 4. Plane in flight
5. Athlete running
6. Satellite in orbit

13. POTENTIAL ENERGY
• Potential energy, or stored energy, is
the ability of a system to do work due to its
position
• It is called potential energy because it has the
potential to be converted into other forms of
energy, such as kinetic energy.

14. Equation of potential energy
PE=U= mgh
PE=potential energy
m= mass
g= gravity
h=height

15. Examples of Potential Energy
Water stored in a dam

16. Gas cylinder

18. Examples of potential energy
1. Glass of milk
2. Water stored in a dam, store at a height
3. A car parked at the top of a hill
4. Gas cylinder

19. Energy
Potential kinetic
Energy possessed by moving object Energy possessed by an object at a height
Example
Moving car
Flowing river
Example
Book keep on a table
Water store in a dam

20. Comparison of Kinetic and
Potential Energy

23. PROBLEM
A bullet of mass 0.005 kg is fired from a pistol
with a velocity of 200 m/s. what is the kinetic
energy of the bullet?
Mass of bullet = 0.005 kg
Velocity =200 m/s
Kinetic energy =½ mv2 =½*0.005*(200)2
=100 J