#6 Name W, 11-08-17 Period The complete range of electromagnetic waves placed in order of increasing frequency is _________________. An image that shows regions of different temperatures in different colors is ______________________. (T or F) All EM waves travel at different speeds in a vacuum, and they have different wavelengths and frequencies. (t or F) As wavelength decreases, frequency increases. List the types of EM waves in order of increasing frequency EM Spectrum Thermogram F T Radio – Microwaves – Infrared Rays – Visible – UV Rays – X Rays - Gamma Rays

Unit 4: Waves and EM Waves Chapter 3 Quiz will be Friday, November 10 Chapter 4 Quiz will be Tuesday, November 21 Unit 4 Test will be Wednesday, November 29 Notice CHANGE!

Unit 4: Waves and EM Waves Chapter 3: Electromagnetic Waves Lesson 3: Wireless Communication Pages 96 - 103 SCCCR Standards 8.P.3: The student will demonstrate an understanding of the properties and behaviors of waves 8.P.3A. Waves (including sound and seismic waves, waves on water, and light waves) have energy and transfer energy when they interact with matter. Waves are a repeating pattern of motion that transfers energy from place to place without overall displacement of matter. All types of waves have some features in common. When waves interact, they superimpose upon or interfere with each other resulting in changes to the amplitude. Major modern technologies are based on waves and their interactions with matter. 8.P.3A.6 Obtain and communicate information about how various instruments are used to extend human senses by transmitting and detecting waves (such as radio, television, cell phones, and wireless computer networks) to exemplify how technological advancements and designs meet human needs.

Science and Engineering Practices Unit 4: Waves and EM Waves Chapter 3: Electromagnetic Waves Lesson 2: Waves of the Electromagnetic Spectrum Pages 88 - 95 Science and Engineering Practices 8.S.1A.2 Develop, use, and refine models to (1) understand or represent phenomena, processes, and relationships, (2) test devices or solutions, or (3) communicate ideas to others. 8.S.1A.8 Obtain and evaluate scientific information to (1) answer questions, (2) explain or describe phenomena, (3) develop models, (4) evaluate hypotheses, explanations, claims, or designs or (5) identify and/or fill gaps in knowledge. Communicate using the conventions and expectations of scientific writing or oral presentations by (1) evaluating grade-appropriate primary or secondary scientific literature, or (2) reporting the results of student experimental investigations. 8.S.1B.1 Construct devices or design solutions using scientific knowledge to solve specific problems or needs: (1) ask questions to identify problems or needs, (2) ask questions about the criteria and constraints of the device or solutions, (3) generate and communicate ideas for possible devices or solutions, (4) build and test devices or solutions, (5) determine if the devices or solutions solved the problem and refine the design if needed, and (6) communicate the results.

Explain how radio waves transmit information. Learning Objectives Explain how radio waves transmit information. Explain how cell phones work. Explain how communications satellites work.

Vocabulary Amplitude Modulation A method of transmitting signals by changing the amplitude of a radio wave. (AM) Frequency modulation A method of transmitting signals by changing the frequency of a wave. (FM)

How do radio waves transmit information? P. 97 Radio waves carry information from the antenna of a broadcasting station to the receiving antenna of your radio. Broadcasting signals P. 98 AM waves have relatively long wave lengths and low frequencies which remain constant while the amplitude changes. Because they are easily reflected by the ionosphere, they can be broadcast over long distances. FM waves have higher frequencies and more energy . They pass through the ionosphere without being reflected back to Earth so they do not travel long distances. Because of the higher frequencies, the sound quality is better.

How does a cell phone work? P. 100 Cell phones only work in a system dividing regions into small cells containing towers that relay signals to a central hub. They use high frequency microwaves to send and receive signals. Quality depends on terrain and how close the phone is to a tower.

How does satellite communication work? P. 102 Communication satellites receive radio, television and telephone signals and relay the signals to receivers on Earth. Satellites are limited to only the regions of the Earth they can “see”. It also depends on the weather. Satellite Phones Satellite TV GPS (Global Positioning System)