Forms of Energy

1. Forms of Energy Chapter F3

2. Kinetic and Potential Energy #1 (F62) • ___________ is the ability to cause changes in matter • _________, which is a form of energy, can change solid ice into liquid • There are two basic kind of energy-the energy of __________ and the energy of ____________ • Any matter in motion has _________ energy and the amount of kinetic energy an object has can ___________ quickly • _________ energy is the energy an object has because of where it is or because of its condition • Once movement of an object happens, ___________ is often changed to ____________ energy

3. Kinetic and Potential Energy #2 (F63) • This change if energy form between kinetic and potential is called ______________ of energy • Although energy is often changed from one form to another, the total ___________ of energy doesn’t change • Energy cannot be _____________ or ______________ and this is the law of the ______________ of energy • Using the pictures of the pole vaulter on F62-63, describe three times the form of energy changes • In the case of the tennis ball bouncing, energy is not destroyed at any point, but with each bounce some of the ball’s energy was lost as _________ and ________ • The heat caused by the _________ of the ball hitting the floor _________ the air and the floor slightly • Eventually, the results of bouncing turned all of the ball’s energy into other ________

4. Kinetic Forms of Energy (F64) • The kinetic energy that objects have is also called ____________ energy and is just one form of kinetic energy • _________ energy is another form of kinetic where the movement of molecules of matter produces heat • ___________ energy, also a form of kinetic, is caused by the movement of electrons and produces shocks as well as the picture and sound on a television • ___________ energy from the picture moves to your eyes in waves and ____________ energy is received by your ears through vibrations produced by the television

5. Potential and Chemical Forms of Energy (F64) • Elastic potential energy is the energy __________ in compression springs, stretched rubber bands, and bent vaulting poles-all materials that can be forced into a shape that’s different from its natural shape • Gravitational potential energy is the energy an object has when its in an _____________ or a stored position • Plants absorb ________ energy and store it as chemical energy in the food they make • When a runner starts to run, chemical energy stored in his __________ is changed into _________ and ___________ energy

6. Electric Charges (F68) • Electric energy runs many forms of ____________ and is the energy that produces ___________ • Electric energy is produced by the movement of ___________ • Within an atom, electrons have a __________ charge and protons and a _________ charge and most objects have an ________ number of protons and electrons • But, when an object gains or loses electrons due to an attraction to ____________ in another object, it has an __________ charge • An object that has gained ___________ has a negative charge and an object that has lost electrons has a ____________ charge • Losing electrons can lead to an object’s attracting of electrons to replace the lost electrons and the attraction can be felt as a ________ or even a spark

7. Electric Force #1 (F69) • Most objects have no _________ because they have about the same number of protons and electrons • If an object has a charge, it attracts objects with the ____________ charge • Similar to magnetic force, ________ charges attract each other, and _______ charges repel each other • This attraction or repulsion is called ___________ __________ and like gravitational force it depends on the ____________ of the objects • Two charged objects produce a larger electric force when they are __________ together

8. Electric Force #2 (F69) • Charged objects have ___________ electric energy, and can also be called static electricity because the electrons are not _____________ • When charged objects are close to each other, potential energy can become ___________ energy • If the charges on the objects are the ___________, the objects repel each other and if the charges are ___________, the objects attract each other • If the objects touch or come very close to each other, __________ may flow from one object to another • Electrons flow from ____________ charged objects to ______________ charged objects • The flow of electrons is called __________ ____________ • Once the charge have moved and are ____________, there is no electric force remaining

9. Electric Circuits #1(F70) • A _________ is used in the wire that makes an electric circuits • An electric circuit is any path along which ________ can flow • ________ and _________ are often used as conductors • Metals are good conductors of electric current because their atoms don’t hold ________ tightly and this allows electrons to move along from one _______ to the next • An electric current flows through good conductors with little ___________ • The conductor in a circuit is wrapped with a material called an ___________, which is a material that does not carry ___________

10. Electric Circuits #2 (F70) • Rubber, _________, glass and ______ are good insulators because they _______ the flow of electrons through them • Insulation keeps wires from toughing each other and completing an _______ ________ before the electrons can reach a device; if this does happen it is called a _________ circuit • Some materials do not completely stop the flow of electrons, but may _________ the flow of electrons in some way and are called resistors • Materials that resist electric current are important because they allow electric energy to be __________ into other forms • The filament in a light bulb resists the flow of electrons and produces ________. When it gets hot enough it ________ • Electrons flowing in an electric circuit can produce heat, ________, sound, or __________ and these are all needed to electric devices

11. Magnets & Electricity (F72) • ________ are used to generate, or produce, electricity • Electric currents produce a ___________ field around them • Why will a compass placed next to a wire carrying an electric current point to the wire? • A current-carrying wire wrapped in a coil of more _______ makes a strong magnet • A coil of current-conducting wire wrapped around an _______ bar makes an even stronger magnet • Around the coil is a magnetic field but it is only __________ when electric current flows through the coil and is called an _____________ • The link between electricity and magnetism allows ______ to be produced from electric energy • An electric motor uses electromagnets and by changing the _________ of the electric current back and forth, these electromagnets alternately _______ and ________each other. This causes the motor to turn

12. Light Energy (F76) • Light rays are a form of ________ that can travel through empty space or through some kinds of ________ • Sometimes light energy is ________ when it strikes matter and colors that bounce off objects as a _________ are the colors we see • Objects of a single color absorb all of the colors and _________ only the color of the object • When light passes through a glass window the speed it travels _________ down and this change in speed of traveling light causes light rays to ________ • The bending of light rays is called __________

13. Lenses (F77) • A lens is a piece of clear material that _________ or refracts, light rays passing through it • A _________ lens is thicker in the middle than at the edges and the rays bend toward each other thus making nearby objects appear __________ • A __________ lens is thicker around the edges than in the middle and the rays bend away from each other thus making nearby objects appear ____________

14. Light Waves (F78) • Light energy moves as waves called ____________ waves • Electromagnetic waves are produced when vibrating _________ inside atoms give off __________ • Other types of electromagnetic waves are ________ waves, ___________, ____________ rays, and ____ rays • Electromagnetic waves move fastest when there is no _________ to slow them down, such as in space • Within the range of visible light waves are different wave patterns that humans sense as different __________ of light • We sense long wave patterns as __________, and short wave patterns as _________

15. Sound Waves (F79) • Sound also moves as ________ and are carried by ___________ matter • Sound waves can travel through _______, ___________ and _________ • As sound waves travel through matter, ___________ in the matter move back and forth in the direction the sound wave is moving • As the sound moves forward, the molecules are squeezed together and this is called a ____________ • After the compression passes, pressure on the molecules ____________ and this is called rarefaction • If a sound is continuous, both ____________ and _____________ are repeated over and over • The ___________ with which sound waves move determines the pitch of the sound; the faster the waves, the _________ the pitch • The more the molecules are squeezed during compression, the __________ the sound, or volume is

16. Sound Energy #1 (F80) • Like ________ waves, sound waves are waves of energy moving through ________, and like water waves, sound waves move molecules _______ and ________ without carrying them along with the wave • Because sound waves are ___________ of molecules, molecules must be present for sound to ________ • Where there is no ________, such as in outer space, sound cannot travel • The sounds we hear travel mostly as vibrations of _______ molecules in the air around us

17. Sound Energy #2 (F80) • When sound waves move through ________ materials, such as liquids and solids, they move faster than they do through air • Denser objects also carry sound energy __________ than less dense objects do • Not all solids carry sound vibrations, and those that do are called sound __________ • Materials that do not carry sound vibrations are called sound ____________ • Materials with a lot of air spaces in them, such as fabrics and plastic foam, are good sound ____________

18. Thermal Energy #1 (F84) • Kinetic energy is present in the movement of __________ • In most types of matter, molecules _________ constantly and this kinetic energy of molecules is _________ energy • The average kinetic energy of all the molecules of an object is the object’s _____________ • The ____________ the molecules move, the higher the temperature • The amount of thermal energy depends upon the number of ____________ present (think of a pot and a cup of boiling water)

19. Thermal Energy #2 (F84) • When rapidly moving molecules bump into slowly moving molecules, they ____________ some of their thermal energy to the slower molecules • The transfer of thermal energy from one substance to another is called __________ • Heat always flows from the __________ substance to the __________ substance • Heat can also change the __________ of a substance, making a solid _________ or a liquid ____________

20. Transferring Thermal Energy #1 (F85) • Thermal energy can be transferred, or _________, between objects in three ways: __________, ___________, and ___________ • Conduction is the __________ transfer of heat between objects that _______ (think of a pot on a stove/burner) • Materials that conduct heat easily are called ___________ (such as metals) and materials that do not conduct heat well are called ___________ (such as air)

21. Transferring Thermal Energy #2 (F85) • Convection is heat transfer as a result of the mixing of a __________ or a ________ and often involves the rising of hot water, then cooling and ________ then reheating and rising again • Radiation is the transfer of thermal energy by ____________ waves • Energy from the _______ is transferred to Earth by these waves • Conduction and convection can transfer heat through ________, but only _________ can transfer heat through ___________

22. Chemical Energy #1 (F86) • Chemical energy is the energy stored in the bonds between _______ when they join together to form _________ • Some chemical reactions give off or take in __________ energy • This thermal energy is stored as a form of __________ energy called chemical energy • Chemical energy can be released as ________ energy when molecules break apart

23. Chemical Energy #2 (F86) • Chemical energy can be released as several form of kinetic energy, such as _________ energy or __________ energy • The potential energy of foods is measured in units called _________ • Chemical energy can also be released as ________ and ________ when wood and other fuels are burned