Waves, Light and Sound March 18, 2006 BY: BRIANNA SHIELDS March 18, 2006 BY: BRIANNA SHIELDS

DO NOW(Homework out on desk please)  1. A rainbow is an example of which of the five main types of energy?  2. Sound is an example of which of the five main types of energy?  3. The digestion of food is an example of which of the five main types of energy?  1. A rainbow is an example of which of the five main types of energy?  2. Sound is an example of which of the five main types of energy?  3. The digestion of food is an example of which of the five main types of energy?

GOAL  To explain the relationship between wavelength and frequency  To recognize the electromagnetic spectrum  To explain the relationship between wavelength and frequency  To recognize the electromagnetic spectrum

Electromagnetic Spectrum  Electromagn etic spectrum WAVES OF ELECTRIC particles traveling at the speed of light

Long wavelength Low Energy Low Frequency

Using the Electromagnetic Spectrum  What is visible light found between?  Infrared and uv light  Which color make up the spectrum of visible light?  ROYGBIV- red, orange, yellow, green, blue, indigo, violet  What is visible light found between?  Infrared and uv light  Which color make up the spectrum of visible light?  ROYGBIV- red, orange, yellow, green, blue, indigo, violet

Using the Electromagnetic Spectrum  Which has a longer wavelength? UV or visible  visible  Which has a longer wavelength? Infrared or radio  Radio  Which has a higher frequency? Infrared or microwave  infrared  Which has a longer wavelength? UV or visible  visible  Which has a longer wavelength? Infrared or radio  Radio  Which has a higher frequency? Infrared or microwave  infrared

Using the Electromagnetic Spectrum  Which has a higher frequency? X-rays or cosmic waves  visible  Which has more energy? X-rays or gamma rays  Gamma rays  Which has more energy? radio or microwave  microwave  Which has a higher frequency? X-rays or cosmic waves  visible  Which has more energy? X-rays or gamma rays  Gamma rays  Which has more energy? radio or microwave  microwave

Electromagnetic Spectrum  Longitudinal waves Vibrate in same direction as lengtH

Electromagnetic Spectrum  Transverse waves Vibrate up and down at right angles to their length

Electromagnetic Spectrum  Crest  Trough  Amplitude  Wavelength  Frequency  Crest  Trough  Amplitude  Wavelength  Frequency High point of a wave Low point of a wave Height from center of wave to high or Low point Distance between 2 crests or 2 troughs How many wave cycles pass by in a period of time

Electromagnetic Spectrum  Crest High point of a wave

Electromagnetic Spectrum  trough low point of a wave

Electromagnetic Spectrum  amplitude distance from the center of a wave to either a high point or a low point A A

Electromagnetic Spectrum  wavelength the distance between the crests or troughs of two waves that are next to each other

Electromagnetic Spectrum  Frequency how many wave cycles pass by in a period of time Freq= # cycles /time= ? SEC

Labeling the parts of a wave  Look at the wave on your handout- label the parts as crests, troughs, amplitude or wavelength

Wavelength Problems  Calculating wavelength, frequency and amplitude  Wavelength = the length between 2 peaks or valleys  Frequency = # cycles/ time (sec)  Amplitude= distance from middle to peak or valley  Look at the Side board for an example  Calculating wavelength, frequency and amplitude  Wavelength = the length between 2 peaks or valleys  Frequency = # cycles/ time (sec)  Amplitude= distance from middle to peak or valley  Look at the Side board for an example

Wavelength & Electromagnetic Spectrum Websites  Website 1:Making WavesMaking Waves  Website 2: National Geographic: Wave Simulator--Volvo Oc...National Geographic: Wave Simulator--Volvo Oc...  Website 1:Making WavesMaking Waves  Website 2: National Geographic: Wave Simulator--Volvo Oc...National Geographic: Wave Simulator--Volvo Oc...

Wavelength Problems  Assessment: Handout  find the wavelength, amplitude and frequency of each wave on your handout  Assessment: Handout  find the wavelength, amplitude and frequency of each wave on your handout

Properties of Sound  Type of wave  Longitudinal waves

Properties of Sound  What is it caused by?  Vibrating air molecules

Properties of Sound  How is sound perceived?  Ear drum picks up vibrations in air

Properties of Sound  Through what types of mediums will it travel?  It travel through a solid, liquid, or gas (Fastest through solids)

 Why can ’ t you hear someone shouting if you are on the moon?

Properties of Sound  In what direction does it travel?  In all directions (can bend around corners)

Properties of Sound  When does it bounce off a surface  Echoes created by hard surfaces

Properties of Sound  When is it taken in by a surface  Soft surfaces absorb sound

Soundproofing Rooms  Rooms are soundproofed by adding soft carpets, heavy curtains and soft tiles  “ Soft ” items take in or absorb sound

Properties of Sound  What is the speed at which it travels?  9. Travels at 335 m/sec

Sound Websites  Website 1: A Science Odyssey: You Try It: Radio Transmis...A Science Odyssey: You Try It: Radio Transmis...  Website 2: Interactive Sound Ruler--Flash version [NIDCD...Interactive Sound Ruler--Flash version [NIDCD...  Website 1: A Science Odyssey: You Try It: Radio Transmis...A Science Odyssey: You Try It: Radio Transmis...  Website 2: Interactive Sound Ruler--Flash version [NIDCD...Interactive Sound Ruler--Flash version [NIDCD...

Properties of Light  Type of wave  Transverse

Properties of Light  What is it caused by?  Waves of excited electrons

Properties of Light  How is it perceived or detected in humans?  By the eye

Properties of Light  Through what types of mediums will it travel  Doesn ’ t even need a medium (will travel through space)

Properties of Light  In what direction does it travel?  Straight lines

Properties of Light  When does it bounce off a surface?  Reflection

Properties of Light  When is it taken in by a surface  Abosorption

Properties of Light  What is the speed at which it travels?  300,000 km/sec

What Happens when Light Strikes Matter?  Absorption  Light taken in by matter

Properties of Light  Reflectio n  When light bounces off things:  Mirror  Color

Properties of Light  Transmittanc e  Light passes right through the matter it strikes

Properties of Light Transparent Light passes straight through –window, glass, air

Properties of Light  Translucent Light passes through and is scattered (wax paper, frosted glass)

Properties of Light  Opaque Light cannot pass through them (metal, wood)

Properties of Light  Refraction Bending of light as it passes through different mediums - Light goes slower through high density materials (causing bending)

Properties of Light  Refraction Examples less dense --> more dense = bends towards normal line

Properties of Light  Refraction Examples more dense--> less dense= bends away from normal line

Properties of Light  Refraction Examples Light moving head on between two substances w/ diff. Densities will not refract/bend

Refraction

Light Websites  Catch The Waves Catch The Waves  The Light Stuff The Light Stuff  Catch The Waves Catch The Waves  The Light Stuff The Light Stuff