Presentation on theme: "Labs and Activities for this Presentation:"— Presentation transcript:
1Labs and Activities for this Presentation: NOTE:This presentation was not made for public use. Please do not use this presentation without my permission and the permission of each of the authors of the photographs, quotes, and other materials that they contain.Thank you,Vicki HughesLabs and Activities for this Presentation:Prism Demo
3WAVES OF SOUND AND LIGHT Electromagnetic Waves = can travel through a vacuumExample: light wavesMechanical Waves = must have a medium to travel inExample: sound waves
4Characteristics of Waves Crest = top of a waveTrough = bottom of a wave Wavelength is the distance from crest to crest
5Characteristics of Waves Amplitude is the distance from resting to the top or bottom of a wave.amplituderestamplitude
6Characteristics of Waves Frequency is the number of waves that pass a fixed point in a given amount of time.34215seconds
7Properties of Waves Wave Speed = Wavelength x Frequency The speed of a wave is a product of its wavelength and frequency.What is the formula for Wave Speed?Wave Speed = Wavelength x FrequencyWhat is the formula for Frequency?Wave Frequency = Speed Wavelength
8Properties of Electromagnetic Waves Example Problem: An electromagnetic wave has a wavelength of 3 meters and a speed of 3.0 x 108 m/s. What is its frequency?Wave Frequency = Speed WavelengthWave Frequency = 3.0 x 108 m/s = 1. 0 x 108 Hz m
9Transverse waves = move perpendicular to the path of travel. Types of WavesTransverse waves = move perpendicular to the path of travel.perpendicularLongitudinal WaveLongitudinal waves = move parallel to the path of travel.parallel
10Sound is MechanicalRemember, mechanical waves must have a medium through which they move.This medium can be solid…
13If a tree falls in the forest and nobody is around to hear it, does it make a sound?
14Characteristics of Sound All sounds begin with vibrating matter.
15Characteristics of Sound Ear captures vibrations.How do we hear sounds?Guitar string vibrates.Vibration is transferred to air particles and move away from the string in waves.Auditory Transduction 6:44
16Characteristics of Sound Remember, sounds cannot travel through space…because there is no medium.
17Characteristics of Sound Properties of Sound: SPEEDSpeed of Sound = the distance that sound travels in a given amount of time.Sound travels more slowly than light.BOOM!
18Characteristics of Sound Sounds travels faster in liquids than in gases… and faster in solids than in liquids.
19Characteristics of Sound Loudness is determined by sound intensity.Intensity is a measure of the amount of energy in sound waves.Unit of intensity = decibel (dB)
20Characteristics of Sound Pitch of Sound = how high or low a sound seems to a listener.Waves and Pitch 2:00
21Characteristics of Sound Pitch depends on the frequency of sounds.Frequency = how often something happensThe frequency of waves is the number of waves that pass a fixed point in a given amount of time.
22Characteristics of Sound Unit for frequency = hertz (Hz)Humans can hear frequencies between 20 – 20,000 Hz.
23Characteristics of Sound Doppler Effect = change in frequency when sound waves are moving.Example: As a train approaches it becomes louder and louder, then as it leaves you it becomes softer and softer.
24Electromagnetic Waves Electromagnetic radiation is the transfer of energy by waves traveling through matter or across empty space.Electromagnetic waves consist of vibrating electric and magnetic fields.
25Electromagnetic Waves ACT L18Electromagnetic waves do NOT require a medium…So electromagnetic waves can travel through space.
26Behavior of WavesElectromagnetic waves can also travel through matter just like mechanical waves.They can:Reflect (bounce back)This property is calledreflection.
27Electromagnetic Waves Electromagnetic waves travel through matter just like mechanical waves.They can:Refract (bend through objects)This property is called refraction.Light through a prism 3:22Demo: Prism
28Electromagnetic Waves Electromagnetic waves travel through matter just like mechanical waves.They can:Diffract (bend around objects)This property is called diffraction.
29Electromagnetic Waves Electromagnetic waves travel through matter just like mechanical waves.They can:be transmitted (sent from one place to another)This property iscalled transmission.
30Electromagnetic Waves Electromagnetic waves travel through matter just like mechanical waves.They can:be absorbed (gathered in by an object)This property iscalled absorption.Absorbed light
31Electromagnetic Waves Electromagnetic waves travel through matter just like mechanical waves.They can:scatter (deviate from theiroriginal path)This property iscalled scattering.
32Electromagnetic Waves Electromagnetic waves act like waves most of the time,But sometimes…They act like particles!
33Electromagnetic Waves Photon = energy released when electromagnetic radiation acts like particles and drops to a lower atomic level.
34Electromagnetic Waves The amount of energy in a photon depends on the frequency of the electromagnetic wave that produced it.
35Types of Electromagnetic Waves Electromagnetic Spectrum is the full range of wavelengths.
36Types of Electromagnetic Waves Radio Waveslowest frequenciesused for radio and television broadcasts, microwave ovens, cell phone transmissions, and radar
37Types of Electromagnetic Waves Light WavesIncludes visible light, infrared light, and ultraviolet light.UVinfraredVisible Light
38Types of Electromagnetic Waves Light Waves can be separated using a triangular prism.
39Types of Electromagnetic Waves Visible LightThe only light that humans can see.Visible Light
40Any Questions? ACT L19 only #1 and #3. EOG CH 2 Review Light Drawing https://www.youtube.com/watch?v=Bfn69oMuH4E