Chapter 12 What is Energy Section 1 Vocabulary

Chapter 12 What is Energy? Section 1

Vocabulary • • • energy kinetic energy potential energy elastic potential energy gravitational potential energy mechanical energy

Other Forms of Energy • • • thermal energy chemical energy electrical energy sound energy light energy nuclear energy

“Energy is the ability to______. ” …………do work!

Kinetic Energy Kinetic energy is energy of motion and depends on speed and mass. Examples: • In tennis, energy is transmitted from the racket to the ball. • When you swing a hammer, you give it kinetic energy which does work on the nail.

Potential Energy • Potential energy is the energy that an object has because of the position, shape, or condition of the object.

Elastic Potential Energy • The energy put into stretching items such as a bowstring, springs, and rubber bands. • You can change the shape of these items by “stretching” them which is elastic potential energy.

Gravitational Potential Energy * Lifting an object requires using a force that is against the force of gravity. • You “transfer” energy to the object and give it gravitational potential energy. • Examples: books on a shelf your backpack after you lift it on to your back The amount of gravitational potential energy that an object has depends on its weight and its height!

Mechanical Energy • Mechanical energy is the amount of work an object can do because of the object’s kinetic and potential energy. • Example: Juggler’s pins used in juggling.

Thermal Energy • Thermal energy is all of the kinetic energy due to random motion of the particles that make up an object. • Thermal energy also depends on the number of particles.

Chemical Energy • Energy in food comes from chemical compounds that food is made of. • Compounds such as sugar is formed by joining different atoms together.

Electrical Energy • Electrical energy is the energy of moving electrons, the negatively charged particles of atoms. • Examples: -electrical outlets -plugging in an amplifier into an outlet and turning it on -plugging in electrical appliances and using it

Sound Energy • Sound energy is caused by an object’s vibrations. • Examples: -playing a guitar, the strings vibrate and produces sound

Light Energy • Light energy is produced by the vibrations of electrically charged particles. • Example: -The energy used to cook food in a microwave is a form of light energy.

Nuclear Energy Nuclear energy comes from changes in the nucleus of an atom. • The energy given off by the sun comes from nuclear energy. • Without the nuclear energy from the sun, life on Earth would not be possible.

Demonstration • • Tennis ball Pendulum (necklace) Hammer/nail Flashlight

Summary • Energy is the ability to do work and work equals the transfer of energy. • Kinetic energy is energy in motion and depends on speed and mass. • Potential energy is energy in motion. • Gravitational potential energy depends on weight and height. • Mechanical energy is the sum of kinetic energy and potential energy.