CHAPTER_20_NOTES_FOR_EIGHTH_GRADE_PHYSICAL_SCIENCE.pdf - CHAPTER 20 NOTES FOR EIGHTH GRADE PHYSICAL SCIENCE A WAVE IS ANY DISTURBANCE THAT TRANSMITS

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CHAPTER 20 NOTES FOR EIGHTH GRADE PHYSICAL SCIENCE A WAVE IS ANY DISTURBANCE THAT TRANSMITS ENERGY THROUGH MATTER OR SPACE. ENERGY CAN BE CARRIED AWAY FROM ITS SOURCE BY A WAVE. HOWEVER, THE MATERIAL THROUGH WHICH THE WAVE TRAVELS DOES NOT MOVE WITH THE ENERGY. A MEDIUM IS A SUBSTANCE THROUGH WHICH A WAVE CAN TRAVEL. A MEDIUM CAN BE A SOLID, A LIQUID, OR A GAS. TWO PROPERTIES OF A MEDIUM AFFECT THE SPEED OF A WAVE. 1. DENSITY - AS THE DENSITY OF A MEDIUM INCREASES, THE SPEED OF A WAVE DECREASES. 2. ELASTICITY - A WAVE MOVES FASTER IN A MORE ELASTIC MEDIUM. SOUND WAVES REQUIRE A MEDIUM. IF THERE ARE NO PARTICLES TO VIBRATE, NO SOUND IS POSSIBLE. WAVES THAT REQUIRE A MEDIUM ARE CALLED MECHANICAL WAVES. SOME WAVES CAN TRANSFER ENERGY WITHOUT TRAVELING THROUGH A MEDIUM. VISISBLE LIGHT IS AN EXAMPLE OF A WAVE THAT DOESN'T REQUIRE A MEDIUM. OTHER EXAMPLES INCLUDE MICROWAVES PRODUCED BY MICROWAVE OVENS, TV AND RADIO SIGNALS, AND X RAYS USED BY DENTISTS AND DOCTORS. WAVES THAT DO NO REQUIRE A MEDIUM ARE CALLED ELECTROMAGNETIC WAVES. THE TWO MAIN TYPES OF WAVES ARE TRANSVERSE WAVES AND LONGITUDINAL WAVES. WAVES IN WHICH THE PARTICLES VIBRATE WITH AN UP-AND-DOWN MOTION ARE CALLED TRANSVERSE WAVES. THE PARTICLES IN A TRANSVERSE WAVE MOVE ACROSS, OR PERPENDICULAR TO, THE DIRECTION THAT THE WAVE IS TRAVELING.
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  • Fall '10
  • Angelica Magtibay
  • Light, Wavelength, Wave mechanics

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