Science+Chapter+17,+SOUND+and++LIGHT

Sound and light travel as WAVES of energy.
I. What is Sound A. Sound energy how sound travels 1. Sound is energy made when something vibrates 2. Volume is the loudness of sound 3. The more energy a sound has the greater its volume 4. Measurement of sound is given in decibals 5. Sounds above 100 dB can damage your ears 6. Travels by molecules being compressed, then compressing the molecules nest to them B. Sound waves 1. Pitch the highness or lowness of a sound 2. Number of vibrations per second is _frequency a. High frequency = high pitch b. Slow frequency = low pitch 3 Move in all directions 4. Sound energy can be absorbed or bounced back creating an echo C. Sound transmission 1. The energy travels from place to place, but the matter that carries the energy stays in place 2. Matter that carries sound waves is called medium 3. speed of sound depends on the medium through which it travels 4. Sound travels faster in warm air than cold, solids and liquids than in gas 5.No sound in space because no medium D. Animals and sound 1. Different living things hear different vibrations 2. humans hear 20,000 vibrations per second, dogs 25, 000, bats 100,000 E. Summary: Sound is energy caused by a medium vibrating. It travels in waves.

II. What is Light? A. Light Energy 1. Travels in waves 2. Can travel in empty space 3. Visible light is part of a range of energy called the electromagnetic spectrum electromagnetic spectrum 4. High frequency waves like X-rays carry more energy 5. Low frequency waves like radio waves carry less energy B. Light Waves 1. Travels in a transverse wave. Go to utube video difference between compression and transverse waves 2. Travels much faster than sound waves 3. We feel sunlight energy as heat 4. Laser lights are powerful and therefore can be dangerous C. Absorption, Reflection and Refraction 1. When light hits an object it is absorbed, bounced back or passes through 2. __________, bounces back 3. Amount of light passing through an objects depends if it is: a. Opaque, does not allow light to pass through b. Translucent, some light passes through c. Transparent, allows light to pass through d. Light bends, refracts when it passes from one material to anoth D. Lenses 1. Concave lens, caved in in the center, edges thicker. Objects look smaller 2. Convex lens, thicker in center. Magnifies objects E. Summary : Light is a small part of the electromagnetic spectrum it travels in transverse waves. Object absorb, reflect or refract light waves.

III. Sound Technology A. Hearing aids make sound louder, amplify it B. Cochlear implants change sound waves to electrical impulses

VOCABULARY Lesson 1 Vibration___________________________________________________________________________________________ Volume ___________________________________________________________________________________________ Pitch _ __________________________________________________________________________________________ Frequency _________________________________________________________________________________________ Lesson 2 Reflection _________________________________________________________________________________________ Opaque _________________________________________________________________________________________ Translucent ________________________________________________________________________________________ Transparent ________________________________________________________________________________________ Refraction _________________________________________________________________________________________ Concave lens _______________________________________________________________________________________ Convex lens ________________________________________________________________________________________