WAVES THROUGH MEDIA SC.7.P.10.3 - Recognize that light waves, sound waves, and other waves move at different speeds in different materials. ALSO ASSESSES: SC.7.P.10.2 Observe and explain that light can be reflected, refracted, and/or absorbed. Essential Question: How are light and sound waves affected by the different media they travel through?

BELL RINGER While attending a baseball game of his favorite major league team, John notices that he can see the batter hit the ball before he hears the crack of the bat. Which of the following statements best explains why there is a time lapse between seeing the baseball hit and hearing it? A. Eyes reacting to stimuli faster than ears do. B. Light waves travel in a more direct path than sound waves. C. Sound waves travel more slowly in the air than light waves do. D. Sound waves from other sounds cause interference with sound waves from the bat.

VIDEO https://www.youtube.com/watch?v=uhEaoaZ2v0w Brainpop: “Waves” Brainpop: “Sound” GIZMO: “Longitudinal Waves”, “Basic Prism”

3 Media: Solids, Liquids, and Gases Sketch the molecular arrangement on the back of your notes.

LONGITUDINAL WAVES A SOUND wave that forms by the compression of molecules as it travels through a medium. Sound causes compression waves from side to side in matter. The closer the molecules, the faster sound can travel.

3 Media: Solids, Liquids, and Gases Sound travels faster through solids than liquids, and faster through liquids than through gases.

TRANSVERSE WAVES A light wave travels as Electromagnetic Radiation Light travels the fastest when there is no matter in the way. Slows down in liquids and gases. Light will change speed as it moves from one medium to another.

REFLECTION Reflection is when a light wave bounces off a surface and changes its direction. Reflected sound are called echoes.

REFRACTED Refraction – When light passes from one form of matter to another, it changes speed. Therefore, the image you see will be distorted.

When light hits a surface, some of it is absorbed, or taken in. ABSORPTION When light hits a surface, some of it is absorbed, or taken in. When light is absorbed, it is transformed from light energy to heat energy. (wearing black in the summer)

Left Side: “WE DO”

REVISITING THE BELL RINGER While attending a baseball game of his favorite major league team, John notices that he can see the batter hit the ball before he hears the crack of the bat. Which of the following statements best explains why there is a time lapse between seeing the baseball hit and hearing it? A. Eyes reacting to stimuli faster than ears do. B. Light waves travel in a more direct path than sound waves. C. Sound waves travel more slowly in the air than light waves do. * D. Sound waves from other sounds cause interference with sound waves from the bat.

YOU DO TIME!

YOU DO #1 Brady notices that when he places a straw in a glass of water, the image of the straw in water and the image of the straw outside of the water do not match up. What is the reason for the difference in how the straw looks above and below the water? Light travels faster through water, refracting the image The surface of the water reflects the image of the straw Light travels faster through air, refracting the image of the straw The light is reflected several times in the glass, creating a false image Correct Answer: C

YOU DO #2 In science class, you listen to the sound of a tuning fork after it is hit against a cork. When you place the tuning fork to one end of a piece of wood and your ear to the other, you notice that the sound becomes high pitched. What happened to the sound waves as they went through the wood? They slowed, due to a high pitch echo They slowed, due to more matter in the wood They sped up, creating a higher frequency They sped up, creating a higher wavelength Correct Answer: C

YOU DO #3 Sound waves need a medium to move through in order to keep moving. Through which of the following would sound travel the slowest? Air Metal Water Wood Correct Answer: A