Energy The Nature of Energy

Learning Targets KNOWLEDGE SKILL Reasoning Know that there are different forms of energy SKILL Calculate the potential and kinetic energy of different objects using formulas Reasoning Compare and contrast potential and kinetic energy

Questions to Think About What are the two basic kinds of energy? Examples? What are some of the different forms of energy? Examples?

Unit of Energy = Newton-meter What is Energy? Work Occurs when a force moves an object through a distance Energy The ability to do work or cause change Energy is transferred when objects or organisms do work on other objects Work = Energy Transfer Energy is measured in JOULES (J) Unit of Energy = Newton-meter Also known as Joules (J)

Two General Kinds of Energy Kinetic Energy Transferred Energy Potential Energy Stored Energy

Kinetic Energy Kinetic Energy Kinetic Energy = “MOVING” Energy in motion Kinetic Energy = “MOVING” Depends on MASS and VELOCITY Energy increases as Mass increases Energy increases as Velocity increases Which ball you roll more forcefully? What would you have to do to make the bowling ball move faster? http://www.schooltube.com/video/faddf7cb14ade293baad/BrainPOP-Kinetic-Energy

Calculating Kinetic Energy The mathematical relationship between kinetic energy, mass, and velocity is written like this: IF YOU: Double the Mass = Double the Kinetic Energy Double the Velocity = Quadruple the Kinetic Energy OR

Calculating Kinetic Energy 10-kg wagon moving at 5 m/s 10-kg wagon moving at 10 m/s 20-kg wagon moving at 5 m/s 15-kg wagon moving at 5 m/s Questions Which wagon has the greatest kinetic energy? How do you increase a moving object’s kinetic energy?

How does each object have potential energy? Energy that is stored and held in readiness to do work Potential Energy = “STORED” Elastic Potential Energy Stretched or compressed objects Gravitational Potential Energy Depends on height How does each object have potential energy? http://www.schooltube.com/video/ffbb4a2cbe25e1bd4a99/BrainPOP-Potential-Energy

Calculating Potential Energy Gravitational Potential Energy formula when you know weight and height: Increase WEIGHT = increase PE Increase HEIGHT lifted = increase PE Gravitational Potential Energy formula when you know height and mass instead of weight: Gravitational Acceleration = 9.8 m/s/s

Calculating Potential Energy Hiker climbs 40 meters up a hill and he weighs 680 Newtons A boulder weighs 200 N is poised at the edge of a 100-meter cliff A book has a mass of 15 kg and is ready to drop from a height of 5 meters Questions: How do you know what formula to use? Which object has more potential energy?

Forms of Energy Energy is all around you in many different forms Kinetic and Potential Energy have a variety of different forms Some of the Major Forms of Energy include: Mechanical Energy Thermal Energy Chemical Energy Electrical Energy Electromagnetic Energy Nuclear Energy http://www.schooltube.com/video/617c60f7739a4a8c53b3/BrainPop-Forms-of-Energy

Can occur either as KE or PE Mechanical Energy Can occur either as KE or PE PLYMOUTH Mechanical Energy Associated with the motion or position of an object

Thermal Energy Thermal Energy Total energy of the particles in an object When thermal energy of an object increases, its particles move faster, making it feel warm to the touch Can occur either as PE and KE

Chemical Energy Chemical Energy Potential energy stored in chemical bonds that hold chemical compounds together Stored in chocolate, wood, and wax Stored in foods you eat and cells in your body

Electrical Energy Electrical Energy Moving electric charges that produce electricity

Electromagnetic Energy Travels in waves Waves have electrical and magnetic properties

Nuclear Energy Nuclear Energy Stored potential energy in the core, or nucleus, of an atom Nuclear fission (split) produce electricity Nuclear fusion (join) occurs in the sun and other stars

Answer Questions What are the two basic kinds of energy? Examples? What are some of the different forms of energy? Examples?