1. Warm Up 1.What is the difference between an element and a compound? 2.What is the difference between a uniform and nonuniform mixture?

2. Reading Activity – Rd. p. 64-71 What I know about energy What I want to know about energy What I learned about energy

3. What is energy? Energy is – the ability to cause change. Energy can change – the temperature, shape, speed or direction of an object. You can use the energy of your muscles – to change the speed of a bicycle by pedaling faster.

4. Energy Transformations And Uses Energy transformations – take place all around you. When a car sits in the sun all day – the energy of light waves change to a form of energy that warms the car. Learning to make fires – the chemical energy in wood is used to cook, stay warm and provide light. Today, electrical energy – is changed into thermal energy that warms your home.

5. Brainstorming Energy Brainstorm ways that you use energy every day. First group to list 5 ways gets a point…

6. Kinetic Energy Kinetic energy – is the energy provided by an object in motion. Examples – a football thrown by a quarterback or a skydiver falling towards Earth,

7. How much kinetic energy? Not all moving objects – have the same amount of kinetic energy. The amount of kinetic energy – an object has depends on the mass and speed of an object. Visualizing Kinetic Energy: p. 67, A and B

8. Potential Energy Potential energy – is energy that comes from position or condition. Potential energy IS NOT – energy that comes from motion. Example – a skier at the top of a hill has potential energy. Even though the skier is not moving, there is the potential to move.

9. Relating Kinetic and Potential Energy There is a direct relationship – between the amount of potential energy an object has and the amount of energy that can be transformed into kinetic energy. When a book is placed on the edge of a table – it has potential energy. When the book is pushed off – the energy becomes kinetic. A book placed on a higher shelf – has more potential energy and therefore more kinetic energy as it falls than it would have if it were on a lower shelf.

10. Conserving Energy Law of conservation of energy – energy cannot be created or destroyed. Energy – can only be transformed from one form into another. Energy in the case of a soccer ball: 1.The soccer player has chemical energy in her muscles from eating food. 2.The chemical energy is released as she swings her leg. 3.Her leg now has potential energy. 4.When her foot kicks the ball, her foot’s kinetic energy is transferred to the ball and the ball is set in motion.

11. Class Activity - Charades Potential EnergyKinetic Energy

12. Check for Understanding 1. State the law of conservation of energy in your own words. 2. Compare and contrast potential and kinetic energy. HW: Science Journal p. 71 #3 – You get up in the morning, get dressed, eat breakfast, walk to the bus stop and ride to school. List three different energy transformations that have taken place.