Presentation on theme: "How do you LIGHT Up your world ? Virginia SOL 5.3"— Presentation transcript:
1 How do you LIGHT Up your world ? Virginia SOL 5.3 Part II-Examining Lightwith Hands-On ActivitiesCompiled by, Marjorie Anne WallaceElementary Science Resource Teacher, NNPS & NSF Coop Agreement
2 Welcome to a power point presentation on LIGHT. We will investigate the following:1. What is light?2. What makes up the visible spectrum?3.How does a prism work?4.Are there any hands-on/minds-on activities I can do to learn more?
3 LIGHT Standards Virginia Standards of Learning 5.3a-e: National Science Education StandardsPhysical Science: Content Standard BAs a result of the activities in gradesK-4, all students should develop an understanding of light, heat, electricity, and magnetism.Virginia Standards of Learning 5.3a-e:The student will investigate and understand basic characteristics of visible light and how it behaves.(*Key concepts, 5.3a-e, are listed in your teacher curriculum guide)
4 A light review: Our primary source of light is the sun. Light travels in straight lines at a speed of 186,000miles per second.Light waves travel faster than sound waves.Light energy from the sun travels through space , reaches earth, and some of it turns to heat energy and warms the earth’s air.Light from the sun also travels to the cells of green plants (producers) and is stored as energy.When light reaches an object, it is absorbed, reflected, or passes through it.
5 Sensing Light Humans have two light detectors. Do you know what they are called?Did you realize cameras and camcorders are light detectors too?
6 SOL query 5th grade 2003 Released Test Item#31 / CORE 1 #31 By passing white light through a prism,you can tell-A that white light is actually a mixture ofdifferent colorsB the mass of the prismC the original source of the lightD that blue light is brighter than whitelight
7 What is light really? Electromagnetic radiation waves Light waves are three dimensionalLight waves vibrate in all planes around a center line.The waves have high points called “crests.”Waves also have low points called “troughs.”*The distance from one crest to the next crest is called a “wavelength.”*The number of waves passing a given point in one second is called the “frequency.”wavelength*A Science Museum of VA:Light Science Activity
8 *Electromagnetic Radiation Electromagnetic radiation can be described in terms of a stream of photons. Each photon is traveling in a wave-like pattern, moving at the speed of light and carrying some amount of energy.The only difference amongst radio waves, visible light, and gamma-rays is the amount of energy of the photons. Radio waves have photons with low energies. Microwaves have a little more energy than radio waves. Infrared has still more energy.As we move down the chart we see visible, ultraviolet, X-rays, and gamma-rays whose photon energies gradually increase.Gamma and Cosmic rays have the highest energy waves.*Slide info from NSTA 2004 conference
9 Remember radio waves are long…and gamma rays are small Radio-TV -Microwave- Infrared - VISIBLE -Ultraviolet -X-rays - Gamma- Cosmic
10 Radio (Longest electromagnetic waves) Emitted byAstronomical ObjectsRadio Station TransmittersDetected byGround based radio telescopes*If you turn on a radio,, it will convert the radio wave energy into sound energy.
11 TelevisionShorter than radio, also used to carry messages (pictures & sound) to our TV sets.*We can sense the TV waves around us with our televisions.
12 Microwave Emitted by: Detected by Gas clouds collapsing into stars Microwave OvensRadar StationsCell PhonesDetected byMicrowave TelescopesFood (heated)Cell phonesRadar (systems)
13 Infrared (Heat or Thermal) Are you a source of infrared? YES you are! Emitted bySun and stars (Near)TV Remote ControlsFood Warming Lights (Thermal)*Everything at room temperature or above,=HEATDetected byInfrared CamerasTVs, VCRs,Your skin
14 Let’s take a look at Herschel’s Experiment Discovered Invisible LightIn 1800, Herschel places his control thermometer just outside the red end of the spectrumResult: The outside thermometer registered the highest temperature
15 Let’s set up Herschel’s Experiment Set up of Box Design for Conducting the Herschel Experiment.
16 Conducting Hershel’s Experiment Place a sheet of white paper inside a cardboard boxTape three thermometers together and place inside boxCut a small notch in the top of the box and position a glass prism so that the spectrum is projected inside the boxArrange the thermometers so that one is just outside the red end of the spectrum, with no visible light falling on it
17 Visible Each color is a different size wave Visible Each color is a different size wave. Red the longest & violet the shortestEmitted byThe sun and other astronomical objectsLaser pointersLight bulbsDetected byCameras(film or digital)Human eyesPlants (red light)TelescopesRoyG.Biv
18 Prism Power: Roy G. Biv Activity *PASCO Probe Activity OR*AIMS:Primarily Physics:Prism Power Activity*What happens when light shines through prisms?Materials :prism, PASCO “wave it,”equipment, paper, +7 Roy G. Biv crayon colors,1. Give handouts. Darken the room and turn on light source. What color is the light? If I use a prism can you predict what will happen to the light?2.Now use the prism. What color is the light?3. Color in your hand out to match the spectrum.
19 Ultraviolet Sunburn / black light He can get skin cancer!Emitted byTanning booths (A)The sun (A)Black light bulbs (B)UV lampsDetected bySpace based UV detectorsUV CamerasFlying insects (flies)
20 X-ray Emitted by Detected by Astronomical objects X-ray machines CAT scan machinesOlder televisionsRadioactive mineralsAirport luggage scannersDetected bySpace based X-ray detectorsX-ray filmCCD detectors
21 Chandra X-ray Observatory Chandra is designed to observe X-rays from high energy regions of the universe, such as the remnants of exploded stars.The most sophisticated observatory built to date.Deployed by the Space Shuttle Columbia on July 23, 1999,Chandra X-ray Observatory*Slide from 2004 NSTA Conference
22 Gamma Ray (Short electromagnetic waves but more energetic) Emitted byRadioactive materialsExploding nuclear weaponsGamma-ray burstsSolar flaresDetected by--Geiger countersGamma detectors and astronomical satellitesMedical imaging detectors
23 Sources of g-ray Emission • Black holes• Active Galaxies• Pulsars• Diffuse emission• SupernovaeGamma-ray bursts• Unidentified
24 COSMIC Rays (The highest energy waves and the deadliest) Cosmic rays come from deep space and can pass through the Earth.
25 How big are the waves? A great question! Radio waves= (Buildings to human size);Microwaves(Humans-beetles);Infrared waves(Eye of a needle);Visible waves(microscopic size)!WOW! All the rest are the size of molecules, atoms, atomic nuclei and smaller..
26 Part III looks at: reflection and refraction of LIGHT. Part I examines: what is light? Waves, opaque, transparent,& translucent, & sources of light around us.Special thanks to NSTA Conference workshops on light!