1. WORK AND ENERGY

2. Work Work is said to be done whenever the application of the force produces a change. A change can be the change in velocity position shape temperature

3. ENERGY The ability to do work is called energy.

4. Different Kinds of Energy Kinetic Energy Potential Energy

5. Kinetic Energy The ability to do work based on motion is called kinetic energy

6. Potential Energy The energy possessed by objects because of their position or shape.

7. Identify Kinetic and Potential Energy

8. An object can have both potential and kinetic energy. An aeroplane flying at a height has both potential and kinetic energy

9. The sum of the potential and kinetic energies of an object is called mechanical energy.

10. Energy can neither be created nor destroyed. It can only be converted from one form to another or transferred from one object to another. Rubbing Palms produces heat energy.

11. Work- Formula How much work is done – depends on the force applied to produce the motion.

12. The amount of work done Depends on The force applied to do the work. The distance travelled Therefore work done= force X distance

13. Unit of Work Unit of Force- Newton Unit of Distance- Meter Therefore, the unit of Work= Newton- meter Newton-meter is also called Joule in the name of British scientist James Joule.

14. Work done in lifting mass to a height Earth attracts the mass m with a force = mg g is the acceleration due to gravity. h is the distance through which the object has moved.

15. Work done… Therefore the work done in raising the books of mass m to height h is mgh.