2Bell Work 11/29/10Please get a new bell work sheet. Write each statement then decide if they are true or false, if false correct them.Mechanical waves transfer energy through a vacuum.A wave is a disturbance that transfers energy.An example if a longitudinal wave is a water wave.
3Please begin working on your electromagnetic poster. Bell Work 11/24/09Please begin working on your electromagnetic poster.
4Bell work 11/25/09List the colors of the visible light spectrum in order from longest wavelength to shortest wavelength.What are the 7 parts of the electromagnetic spectrum?
5Bell Work 12/2/09 What are EM waves measured in? Give two examples of using a radio wave.Give 3 examples of using a microwave.List the colors of visible light from longest wavelength to shortest wavelength.
6Please use complete sentences Bell Work 11/30/09Please use complete sentencesGive an example of using a radio wave.Give an example of using a microwave.Give an example of using an x-ray.
71.1 VocabElectromagnetic wave – a disturbance that transfers energy through a fieldRadiation – energy that moves in the form of EM waves
8How EM waves form and sources of EM waves Electric and magnetic fields make up EM wavesMany of the EM waves on Earth’s environment come from the Sun.Stars give off EM waves but since they are so far away not many of their waves hit the EarthTechnology is also a source of EM waves
9Bell Work 11/30/10What do electromagnetic waves transfer energy through?What is radiation?How does a microwave cook food?
10Electromagnetic spectrum The range of all EM frequenciesThe spectrum goes from the ______ frequencies to the _______frequencies______-frequency EM waves with more electromagnetic vibrations per second have more energy than _____-frequency EM waves
12Measuring EM WavesEM wave frequency is measured in _____ (Hz)One hertz equals one cycle per ______
13Welcome to December Bell Work 12/1/10 What is the electromagnetic spectrum?State whether each statement is true or false. If false make the statement true.2. Mechanical waves transfer energy through a vacuum.3. A wave is a disturbance that transfers energy.4. Most EM waves are invisible but detectable.
14Radio wavesHave the ______ wavelengths, the ______ frequencies, and the ______ energiesExamples of radio waves are AM/FM radio and broadcast television
16MicrowavesEM waves with ______ wavelengths, higher frequencies, and _____ energy than other radio wavesRadar – radio detection and ranging. Used to control air traffic at airports, analyze ________ conditions and measure the speed of a moving vehicleRadar led to the invention of ________ ovensCell phones – radio transmitter and receiver that uses ________
18Infrared Light Type of EM wave most often associated with ______ Sometimes referred to as _____ raysYou can feel it as warmth coming from the sun, a fire, or a radiatorInfrared lamps are used to provide ______ in bathrooms and to keep food warm after its been cookedSome animals can see in _____ light
20Visible Light The part of the EM spectrum that _____ eyes can see. Longest wavelengths are _____ all the way to violetROY G BIVRed, Orange, Yellow, Green, Blue, Indigo, Violet
21Ultraviolet Light Has more energy than _____ light The waves in this range can ______ your skin and eyesSun block and UV-protection sunglasses are designed to filter out the _______ frequenciesUV light can be used to sterilize medical instruments and food by _____ harmful bacteriaUV light causes skin cells to _______ vitamin D which is essential to good healthUV light is ______ to some animals. Bees and some other insects
23X-rays Has a very ______ frequency and ______ Pass easily through soft tissues of the body, but are absorbed by the _____The _______ pass through exposing the film where there is no boneWhen getting x-rays other parts of the body are covered with a _____ vest to block the x-rays
25Gamma rays ________ frequencies and energies of any ___ waves Produced by some radioactive substances as well as the ____ and other _____Gamma rays can penetrate the soft and the hard tissues of the body, killing normal cells and causing cancer cells to developGamma rays can also be used to kill _____ cells and _____ tumors
27Bell Work 12/3/09Which group from the EM spectrum has the highest frequencies?Which group pass easily through soft tissues of the body, but are absorbed by the bone?What can you use to filter out the high frequencies of UV rays?Which EM wave is most associated with heat?
28Bell Work 12/4/09Predict what would happen if you kept a green plant in the dark for one month. Explain why. (at least 3 sentences)
29Vocab 3.3Incandescence – the production of light by materials at high temperaturesLuminescence – the production of light without the high temperature. Many organisms produce their own visible light through this.
30Bioluminescence – production of light by living organism Bioluminescence – production of light by living organism. These organism produce light from chemical reactions rather than intense heat.Fluorescence – occurs when a material absorbs EM radiation of one wavelength and gives off EM radiation of another.
31Bell Work 12/5/09 What happens to the speed of EM waves in a vacuum? What happens when microwaves encounter water?What produces the most EM waves on Earth?
32Light 3.4 NotesTransmission – the passage of an EM wave through a medium.If the light reflected from objects did not pass through the air, windows, or most of the eye, we could not see the objects
33Absorption – the disappearance of an EM wave into the medium Absorption affects how things look, because it limits the light available to be reflected or transmitted
34How Materials Transmit Light Transparent materials allow most of the light that strikes them to pass through.Translucent materials transmit some light, but they also cause it to spread out in all directions.Opaque materials do not allow any light to pass through them, because they reflect light, absorb light, or both
35Scattering – the spreading out of light rays in all directions, because particles reflect and absorb the lightFog or dust in the air, mud in water, and scratches or smudges on glass can all cause scatteringScattering creates a glare and makes it hard to see even through a transparent material
36Polarization – a quality of light in which all of its waves vibrate in the same direction Polarizing filters reduce glare and make it easier to see objectsPrism – a tool that uses refraction to spread out the different wavelengths that make up white lightPrisms split light into colors by refracting wavelengths in different amounts
37Color Reflection and Absorption The color of an object or material is determined by two factorsthe wavelengths it absorbs and those it reflectsThe wavelengths present in the light that shines on the object
38A material that reflects all wavelengths of visible light appears white A material that absorbs all wavelengths of visible like appears blackA green lime absorbs most wavelengths but reflects green, so the lime looks green
39Primary Colors of Light The human eye can detect only 3 color bands: red, green, and blueYour brain perceives these three colors and various mixtures of them as all the colorsPrimary colors – red, green, and blue – can be mixed to produce all the possible colors
40Primary PigmentsMaterials can be mixed to produce colors just as light canMaterials that are used to produce colors are called pigmentsPrimary pigments – cyan, yellow, and magenta
41Bell Work 12/8/09 What color is something that absorbs all the colors? What color is something that reflects all colors?If an object absorbs most wavelengths but reflects violet what color will it be?
42Bell Work 12/9/09 – (fill in the blanks) Bioluminescent animals produce light through _________.When light is absorbed into a medium, the waves ________ in the medium.The primary pigments create colors through _____________ mixing.An electromagnetic wave transfers energy through a ______.Most of the visible EM waves on Earth come from the ______.