1. Ch.9, Sec.1 – What Is Energy?  energy: the capacity to do work Energy and Work: Working Together Energy and Work: Working Together - work is done when a force causes an object to move in the direction of the force - when one object does work on another, energy is transferred from the 1st object to the 2nd - therefore, work is a transfer of energy! - energy is expressed in units of Joules (J) - all matter has atoms; therefore, all matter has energy!!!!!

2. Ch.9, Sec.1 – What Is Energy? Kinetic Energy Kinetic Energy  kinetic energy: the energy of motion - all moving objects have kinetic energy & this energy can be used to do work - kinetic energy can be found using the following formula: KE = mv² KE = mv² 2 - m stands for mass in kilograms, v stands for the objects speed (the more speed & mass of an object means greater kinetic energy) - speed has a greater effect on kinetic energy than mass (faster cars cause greater crashes)

3. Ch.9, Sec.1 – What Is Energy? Potential Energy Potential Energy  potential energy: the energy that an object has because of the position, shape, or condition of the object - any object elevated from the ground has gravitational potential energy (the more weight & height means greater GPE) - gravitational potential energy can be found using the following formula: GPE = weight x height - GPE is expressed using Newton-meters - height of GPE is a measure of how far an object has to fall

4. Ch.9, Sec.1 – What Is Energy?

6. Mechanical Energy Mechanical Energy  mechanical energy: the total energy of motion and position of an object (can be all potential, all kinetic, or some of each) - mechanical energy can be found using the following formula: ME = PE + KE ME = PE + KE - mechanical energy remains the same unless it transfers some of its energy to another object - even if mechanical energy stays the same, potential or kinetic energy can increase or decrease

7. Ch.9, Sec.1 – What Is Energy? Other Forms of Energy Other Forms of Energy  thermal energy: all of the kinetic energy due to random motion of the particles that make up an object - there’s more kinetic energy in gases than solids because of the molecular movement

8. Ch.9, Sec.1 – What Is Energy?  chemical energy: the energy of a compound that changes as its atoms are rearranged - chemical energy is a form of potential energy because it depends on the position & arrangement of the atoms in the compound

9. Ch.9, Sec.1 – What Is Energy?  electrical energy: the energy of moving electrons - changing positions of magnets at power plants provides electrical energy (potential energy too)

10. Ch.9, Sec.1 – What Is Energy?  sound energy: the energy caused by an object’s vibrations (potential energy turned into kinetic energy)  light energy: energy produced by the vibrations of electrically charged particles - light energy can travel through a vacuum! (an area with little or no atoms, like deep space)

11. Ch.9, Sec.1 – What Is Energy?  nuclear energy: the energy that comes from changes in the nucleus of an atom - energy can be from fusion where atoms can join together to create electrical energy (Sun) - energy can be from fission where atoms can be split apart in the nucleus to create a lot of potential energy (uranium in the atomic bombs)

12. Ch.9, Sec.1 – What Is Energy? Are the following types of energy kinetic or potential? Are the following types of energy kinetic or potential? 1. thermal energy = _____________________ 2. chemical energy = _____________________ 3. electrical energy = _____________________ 4. sound energy = _____________________ 7. light (radiant) energy = _____________________ 8. nuclear energy = _____________________ kinetic energy 5. mechanical energy = _____________________ 6. gravitational energy = _____________________ potential energy