1. PS-6.1: explain how the law of conservation of energy applies to the transformation of various forms of energy PS-6.2: explain the factors that determine potential and kinetic energy and the transformation of one to the other Energy

2. Everything we do requires energy Sleeping, eating, running, standing still- all require energy Many different kinds of energy Mechanical energy is energy due to the position of something or the movement of something Chemical energy is a type of energy associated with atoms, ions, and molecules and the bonds they form Electrical energy is energy associated with current and voltage Thermal energy is associated with the movement of molecules Light energy is energy that associated electromagnetic waves Sound energy is energy associated with longitudinal mechanical waves

3. Energy Different kinds of mechanical energy Kinetic or potential or the sum of the two Kinetic Energy is the energy a moving object has because of its motion Depends on object’s mass and speed Greatest when the speed is greater Greater when the mass is greater Kinetic energy (J) = 1/2mass (kg) * [speed (m/s)] 2 KE=1/2mv 2

4. Energy Pg. 102 A jogger with a mass of 60.0kg is moving at a speed of 3.0m/s. What is the jogger’s kinetic energy? Do practice problems on your own

5. Energy Potential energy is the energy of position Gravitational potential energy is greater when the height is greater Gravitational potential energy is greater when the weight of the object is greater Types of Potential energy Elastic potential energy is energy stored by something that can stretch or compress Chemical potential energy is energy stored in chemical bonds Gravitational potential energy is the energy stored by objects due to their position above Earth’s surface

6. Gravitational Potential Energy GPE depends on object’s mass and height above ground Gravitational potential energy(J) = mass(kg) * acceleration of gravity(m/s 2 ) * height(m) GPE = mgh g = 9.81m/s 2 Pg. 104 What is the gravitational potential energy of a ceiling fan that has a mass of 7.0kg and is 4.0m above ground? Do practice problems on your own

7. Energy Law of Conservation of Energy Energy cannot be created or destroyed Energy can be converted from one from to another but the amount of total energy will never change Examples of changing energy Ball dropping Pendulum swinging