2. © 2004 Plano ISD, Plano, TX

6. During every waking and sleeping moment of our lives, we are bombarded with of energy.

7. © 2004 Plano ISD, Plano, TX Most energy waves collide with us or pass right through us without any notice on our part. Waves carry energy, but not matter; however, matter can be used to transfer energy.

8. © 2004 Plano ISD, Plano, TX The matter used to transport the wave is a medium. What is the medium? mechanical waves Waves that use matter to transfer energy are mechanical waves.

9. © 2004 Plano ISD, Plano, TX What is the medium?

10. © 2004 Plano ISD, Plano, TX What is the medium?

11. © 2004 Plano ISD, Plano, TX In the 15th century, Leonardo da Vinci observed that while waves move, the medium (water) does not, “like the waves made in a field of grain by the wind, where we see the waves running across the field while the grain remains in place.”

12. © 2004 Plano ISD, Plano, TX Water,sound, and earthquake waves are examples of mechanical waves.

13. © 2004 Plano ISD, Plano, TX Mechanical waves can be classified according to the direction of the motion of matter in relation to the direction of wave motion.

14. © 2004 Plano ISD, Plano, TX Mechanical waves in which matter moves up and down or back and forth at right angles compared to the direction of wave movement are transverse waves. Click here to see transverse waves in action!

15. © 2004 Plano ISD, Plano, TX Mechanical waves in which medium matter moves forward and backward in the same direction the wave travels are longitudinal or compressional waves. Click here to see compressional waves in action!

16. © 2004 Plano ISD, Plano, TX Amplitude: Distance between crest and trough Wavelength: Distance between 2 crests OR 2 troughs Frequency: waves per second (measured in Hertz/Hz) Speed: distance per second Properties of Waves

17. © 2004 Plano ISD, Plano, TX Properties of Waves

18. © 2004 Plano ISD, Plano, TX electromagnetic waves Waves that do not require matter to transfer energy are electromagnetic waves. Electromagnetic waves can travel through a medium, but they can also travel in space or through a vacuum.

19. © 2004 Plano ISD, Plano, TX Radio waves, X-rays, microwaves, and visible light waves are examples of electromagnetic waves. They can all travel through empty space and they all travel at the same speed. This speed is sometimes called The Speed of Light.

20. © 2004 Plano ISD, Plano, TX Electromagnetic waves are produced by charged particles that move. Energy from EM waves is called EM RADIATION. Even though EM waves have the same speed, they have different wavelengths and frequencies. (look at the EM spectrum)

21. © 2004 Plano ISD, Plano, TX Electromagnetic Spectrum © 2000 Microsoft Clip Gallery

22. © 2004 Plano ISD, Plano, TX Review the information on waves by filling in the concept map.

23. Waves do not move or carry energy include examples such as transfer energy through matter called a ________ includes transfer or carry mechanical waves matter can be classified into two categories electromagnetic waves medium solids, liquids, gasses longitudinal or compression waves transverse waves matter forward and backward in the same direction of wave movement matter up and down or back and forth at right angles compared to the direction of wave movement move to transfer do not require include examples such as matter energy are further classified into are a special type of

24. © 2004 Plano ISD, Plano, TX Bibliography Macaulay, David. (1988). How things work. Boston: Houghton Mifflin Company. pp. 186 Resnick, Halliday, Krane. (1992). Physics. 4th Edition, Volume 1. New York: John Wiley & Sons, Inc. pp. 417-418. “What are waves?” (2002). Texas Science. New York: Glenco McGraw-Hill,pp. 186-187.