* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Lesson 2 - Kinetic and Potential Energy - Hitchcock
William Flynn Martin wikipedia , lookup
Open energy system models wikipedia , lookup
Photoelectric effect wikipedia , lookup
Dark energy wikipedia , lookup
Energy subsidies wikipedia , lookup
Energy storage wikipedia , lookup
100% renewable energy wikipedia , lookup
Low-Income Home Energy Assistance Program wikipedia , lookup
Public schemes for energy efficient refurbishment wikipedia , lookup
Work (physics) wikipedia , lookup
Zero-energy building wikipedia , lookup
Low-carbon economy wikipedia , lookup
World energy consumption wikipedia , lookup
Alternative energy wikipedia , lookup
Energy Charter Treaty wikipedia , lookup
Gibbs free energy wikipedia , lookup
International Energy Agency wikipedia , lookup
Energy policy of the United Kingdom wikipedia , lookup
Energy returned on energy invested wikipedia , lookup
Energy harvesting wikipedia , lookup
Distributed generation wikipedia , lookup
Energy policy of Finland wikipedia , lookup
Regenerative brake wikipedia , lookup
Energy efficiency in transport wikipedia , lookup
Life-cycle greenhouse-gas emissions of energy sources wikipedia , lookup
Negawatt power wikipedia , lookup
Energy in the United Kingdom wikipedia , lookup
Internal energy wikipedia , lookup
Energy policy of the European Union wikipedia , lookup
Energy applications of nanotechnology wikipedia , lookup
Energy efficiency in British housing wikipedia , lookup
Energy Independence and Security Act of 2007 wikipedia , lookup
Kinetic energy wikipedia , lookup
Unit 2 Lesson 2 Kinetic and Potential Energy Copyright © Houghton Mifflin Harcourt Publishing Company Unit 2 Lesson 2 Kinetic and Potential Energy On the Move What is kinetic energy? • Energy is the ability to cause change. There are different forms of energy. One form is kinetic energy, the energy of motion. • Every moving object has kinetic energy. The faster an object moves, the more kinetic energy it has. If two objects move at the same speed, the object that has more mass will have more kinetic energy. Copyright © Houghton Mifflin Harcourt Publishing Company Unit 2 Lesson 2 Kinetic and Potential Energy How is the kinetic energy of an object calculated? • The kinetic energy of an object equals one-half the object’s mass (m) times the square of its volume (v). • Kinetic energy = 1 mv2 2 • When mass is expressed in kilograms (kg) and speed in meters per second (m/s), kinetic energy is expressed in joules (J). Copyright © Houghton Mifflin Harcourt Publishing Company Unit 2 Lesson 2 Kinetic and Potential Energy It Could Change What determines the potential energy of an object? • An object that is not moving can still have energy. Potential energy is the energy an object has because of its position, condition, or chemical composition. • An object has elastic potential energy when it has been stretched or compressed. Elastic potential energy is stored in a stretched spring or a rubber band. Copyright © Houghton Mifflin Harcourt Publishing Company Unit 2 Lesson 2 Kinetic and Potential Energy What determines the potential energy of an object? • An object has gravitational potential energy due to its position above the ground. An object held above the ground has the potential to fall. The higher the object is above the ground, the greater its gravitational potential energy. • Potential energy that depends on an object’s position is referred to as mechanical potential energy. • A substance stores chemical potential energy as a result of its chemical bonds. Some of that energy can be released during chemical reactions. Copyright © Houghton Mifflin Harcourt Publishing Company Unit 2 Lesson 2 Kinetic and Potential Energy How is the gravitational potential energy of an object calculated? • The gravitational potential energy of an object equals its mass (m) times its height above the ground (h) times the acceleration due to Earth’s gravity (g). • Gravitational potential energy = mgh • An object’s mass is expressed in kilograms. An object’s height above the ground is expressed in meters. The acceleration due to Earth’s gravity is 9.8 m/s2. • Potential energy is expressed in units of joules. Copyright © Houghton Mifflin Harcourt Publishing Company Unit 2 Lesson 2 Kinetic and Potential Energy How is the gravitational potential energy of an object calculated? • When does the bouncing ball have zero gravitational potential energy? Copyright © Houghton Mifflin Harcourt Publishing Company Unit 2 Lesson 2 Kinetic and Potential Energy It All Adds Up! How is the mechanical energy of an object calculated? • A moving object can have both kinetic and potential energy. Mechanical energy is the energy possessed by an object due to its motion and position. • The sum of an object’s kinetic energy (KE) and mechanical potential energy (PE) is its mechanical energy (ME). • ME = KE + PE Copyright © Houghton Mifflin Harcourt Publishing Company Unit 2 Lesson 2 Kinetic and Potential Energy How is the mechanical energy of an object calculated? • If the object’s only potential energy is gravitational potential energy, you can use the following equation to find mechanical energy. • ME = 1 mv2 + mgh 2 Copyright © Houghton Mifflin Harcourt Publishing Company Unit 2 Lesson 2 Kinetic and Potential Energy How is the mechanical energy of an object calculated? • As the basketball falls to the ground, its kinetic energy increases and its gravitational potential energy decreases. However, its mechanical energy remains constant. Copyright © Houghton Mifflin Harcourt Publishing Company