What is Energy? Key Concepts: Vocabulary: Explain the relationship Chapter 5, Section 1 Pages (124-131) Explain the relationship between energy and work Compare kinetic and potential energy Vocabulary: Describe different forms of energy energy Kinetic energy potential energy mechanical energy

Energy p. 124 The ability to do work Work is done when a force causes an object to move in the direction of the force Maglio does work on his bat by exerting force on it. The bat does work on the ball by exerting force on it. The ball does work on a spectator’s baseball mit by exerting a force on it!! “A HOME RUN”

The energy of an object that is due to the object’s motion Kinetic Energy p. 125 The energy of an object that is due to the object’s motion True or False? As the baseball flies through the air, it has kinetic energy. True All moving objects have kinetic energy. True

Kinetic energy depends Speed has a greater effect How can you measure kinetic energy? Lets look at the math KE = Mass (of object) x Speed (m/s)² 2 m = mass (kilograms) v = speed (meters per second) J = joules (unit for energy) Kinetic energy depends on mass and speed Speed has a greater effect on kinetic energy than mass does.

Joule A joule is approximately the amount of energy necessary to lift an apple one meter. A tennis serve: 75 J Fastball pitch : 120 J Football pass : 150 J Joule Tm. P 125

The following video clip takes a look at Potential and Kinetic energy In our every day lives. Lets take a look

Potential and kinetic energy in the real world Take a look! Galileo's "Stop Height": Gravity and Potential and Kinetic Energy at Work

The energy an object has because of its position Potential Energy p. 126 The energy an object has because of its position

Which diver has greater potential energy? Gravitational potential energy = weight x height (distance to water) (this varies) (10 meters) (1 meter)

This video clip looks at Energy Transformations

Potential, Kinetic and Mechanical energy transformations.

Mechanical Energy p. 127 The amount of work an object can do because of its potential and kinetic energies. Mechanical Energy p. 127

Thermal Energy p. 128 All the kinetic energy due to random motion of the particles that makeup an object.

Chemical Energy p. 128 That part of the energy in a substance that can be released by a chemical reaction Energy stored in the chemical bonds of molecules.

Electrical Energy p. 129 Energy of moving electrons.

Sound Energy p. 129 Waves of energy created when an object vibrates

Light Energy Light is produced by the vibrations of electrically charge particles. Light Energy Part of the electromagnetic spectrum we can See.

Nuclear Energy Two types of nuclear energy: Energy that comes from the nucleus of an atom. Fusion: Two types of nuclear energy: A process in which two smaller atomic nuclei fuse into one larger nucleus and release energy. Fission: The splitting of a large nucleus into two smaller nuclei with the emission of large amounts of energy.

The animation of a nuclear fusion: The animation of a nuclear fission: Energy given off by the sun. Also the source of power for the hydrogen bomb. The animation of a nuclear fission: This type of nuclear energy is used to generate electrical energy at nuclear power plants. Also the type of bombs dropped on Hiroshima and Nagasaki.

HM 16-5: Test explosion of a hydrogen bomb HM 16-5: Test explosion of a hydrogen bomb. (Image from Department of Defense) Nuclear Fusion