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Falcon Focus. Use the graph to answer #1 (8-5.1) What is the average speed of the ball? 2 m/s 6 m/s 8 m/s 72 m/s. Essential Question. 8-6.1: How would you explain or describe a wave?. 8-6.1 Recall that waves transmit energy but not matter. Waves. What is a Wave?.
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Falcon Focus • Use the graph to answer #1 • (8-5.1) What is the average speed of the ball? • 2 m/s • 6 m/s • 8 m/s • 72 m/s
Essential Question • 8-6.1: How would you explain or describe a wave?
8-6.1 Recall that waves transmit energy but not matter Waves
What is a Wave? • Wave is a repeating disturbance or vibration that transfers or movesenergy from place to place.
Properties of a Waves • Waves are created when a source of energy (force) causes a vibration. • A vibration is a repeated back-and-forth or up-and-down motion. • Waves carry energy through empty space or through a mediumwithout transporting matter.
Property of a Wave • While all waves can transmit energy through a medium, certain waves can also transmit energy through empty space. • What is a medium? A medium is a material through whichwaves can travel. It can be a solid, liquid, or gas. • When waves travel through a medium, the particles of the mediumare notcarried along with the wave. • When there isno medium, certain waves (electromagnetic) can travel through empty space.
Closure and Homework • Answer the following questions for Homework on a separate sheet of paper. (Monday) • What causes waves? What do waves carry? • What is a wave? • What is a medium? • Give different examples of waves and the mediums they travel through. • What types of waves travel through a medium and what type of waves do not require a medium?
Flashback Quiz • 1. Name the three types of boundaries. • 2. Explain what happens within the three types of boundaries. • 3. Name what forms from each type of boundary. • 4. Name the stresses that go along with each type of boundary. • 5. Name the faults that go along with each type of boundary.
Falcon Focus • (8-5.1) The total displacement for the object was… • 0 meters • 20 meters • 45 meters • 90 meters
Falcon Focus • (8-5.4) Which would not be a way to cause a moving object to move faster? • A increasing the force applied to the object. • B. removing some of the mass of the object. • C. applying force in the opposite direction. • D. adding another force to the object in the same direction. • Essential Question: • How would you explain the difference between mechanical and electromagnetic waves?
8-6.2 Distinguish between mechanical and electromagnetic waves.
There are two types of waves: mechanical and electromagnetic waves:
Mechanical Waves • Mechanical waves (M & M candy) Medium requires a medium • Mechanical waves require the particles of the medium to vibrate in order for energy to be transferred.
Electromagnetic Wave • Electromagnetic waves (E & E) Empty Space • Electromagnetic waves are waves that can travel through matter or empty space where matter is not present. • Does Not Require a Medium
Mechanical Waves • There are 2 Types of Mechanical Waves: • Transverse Waves • Compressional or Longitudinal Waves
Transverse Waves • Mechanical waves in which the particles of matter in the medium vibrate by moving back and forth and perpendicular (at right angles) to the direction the wave travels are called transverse waves..
Transverse Waves • A transverse wave is made up of crests and troughs. • Crest: the highest point of a transverse wave • Trough: the lowest point of a transverse wave
Transverse Waves • Examples of mechanical transverse waves might include water or ocean waves and waves created from a rope. • Electromagnetic waves are transverse waves that can travel without a medium through empty space.
Compressional/Longitudinal Waves • Mechanical waves in which the particles of matter in the medium vibrate by pushing together and moving apart parallel to the direction in which the wave travels are called compressional or longitudinal waves.
Compressional/Longitudinal Waves • A compressional wave is made up of compressions and rarefactions that travel through a medium. • Compressions: the part of the wave that pushes or compress together • Rarefactions: the part of the wave that spreads or move apart
Compressional/Longitudinal Waves • Examples of mechanical compressional/longitudinal waves might include sound waves, slinky spring, and some seismic waves.
Homework/Closure • Answer the following questions on another sheet of paper for Homework. (Tuesday) • Compare and contrast mechanical and compressional/longitudinal waves. Give an example of each type. • Compare and contrast a transverse wave and compressional waves. Give an example of each type. • Describe the motion of a buoy when a water wave passes. Does it move the buoy forward? Explain Why? • Explain how you could model a compressional/longitudinal wave using a coiled spring or slinky toy. • List the characteristics of a mechanical wave. • Extra Credit: • Why do boats need anchors if ocean waves do not carry matter forward? • The average speed of sound in water is 1,500 m/s. How long would it take a sound wave to travel 9,000 m? (Use the steps to work out this problem)
Flashback Quiz: Types of Rocks • 1.(8-3.4) Rocks that form below Earth’s surface and cool slowly are called _. • a.extrusive igneous • b.extrusive metamorphic • c.intrusive igneous • d.intrusive metamorphic • 2.(8-3.4) More often than metamorphic or igneous rocks, sedimentary rocks have — • a.a glassy appearance • b large quartz crystals • c many holes from trapped gases • d numerous fossils • 3. (8-3.4) In addition to heat, which of the following changes granite to gneiss? • a) acid • b) erosion • c) pressure • d) water • 4. The rock cycle indicates all of the following about each type of rock EXCEPT • A. breaks at the focus • B. changed by forces at Earth’s surface • C. form other rocks • D. provide materials to make other rocks • 5. (8-3.4) The process of changing a rock from a solid into magma or lava due to high heat is known as_ • A. crystallization B. deposition • C. erosion D. melting
Falcon Focus • (8-5.3) What is the primary force that Student 1 works against in order to lower Student 2? • friction • gravity • magnetism • pressure
Just do the Essential Question for today (8-6.3) How would you illustrate and contrast the two types of mechanical waves?
Learning Object • 1. Students will focus on the following terms: friction, gravity, balance force, unbalance force, and inertia. • 2. Students will describe the two categories of waves. • 3. Students will demonstrate the two types of mechanical waves. • 4. Students will complete an activity sheet for understanding. • 5. Students will complete the flashback quiz. • 6. Closure • 7. Students will start on standard 8-6.3
Wave Quiz • 1. Waves transmit or carry ________ but not ________________. • 2. What is a wave? • 3. How are waves created? • 4. Describe the 2 types of waves. • 5. What is a medium?
6. What are the 2 types of Mechanical Waves? • 7. What is the highest point and lowest point called in a transverse wave? • 8. What is the area called when the parts come together and what is it call when they spread far apart in a compressional wave?
9. How does transverse waves move? • 10. How does compressional waves move?
8-6.3. Summarize factors that influence the basic properties of waves (including frequency, amplitude, wavelength, and speed).
The basic properties of waves are influenced by several factors.
Frequency • Frequency is a measure of how many waves pass a point in a certain amount of time. • The higher the frequency, the closer the waves are together and the greater the energy carried by the waves will be. • The lower the frequency, the farther apart the waves are.
Amplitude • Amplitude is a measure of the distance between a line through the middle of a wave and a crest or trough. • The greater the force that produces a wave, the greater the amplitude of the wave and the greater the energy carried by the wave. • In a transverse wave the higher the wave, the higher the amplitude. • Sounds with greater amplitude will be louder; • light with greater amplitude will be brighter.
Wavelength • Wavelength is a measure of the distance from the crest on one wave to the crest on the very next wave or it can be from trough to trough. • Shorter wavelengthsare influenced by the frequency. • A higher frequencycauses a shorter wavelength and greater energy.
Speed • Speed is a measure of the distance a wave travels in an amount of time. • The speed of a wave is determined by the type of wave and the nature of the medium. • As a wave enters a different medium, the wave’s speed changes. • Waves travel at different speeds in different media.
Speed • All frequencies of electromagnetic waves travel at the same speed in empty space.
Homework/Closure • Answer the following questions on another sheet of paper for Homework. (Thursday) • Describe the difference between a compressional wave with a large amplitude and one with a small amplitude. • Describe how the wavelength of a wave changes if the wave slows down and its frequency doesn’t change. • Form a hypothesis to explain why a sound wave travels faster in a solid than in a gas. • You make a transverse wave by shaking the end of a long rope up and down. Explain how you would shake the end of the rope to make the wavelength shorter. How would you shake the end of the rope to increase the energy carried by the wave? • Illustrate a transverse wave including the following properties: crest, trough, amplitude, wavelength, and frequency.
Types of Rock Flashback Quiz • 1. What processes do igneous rocks go through? • 2. What processes do metamorphic rocks go through? • 3. What processes do sedimentary rocks go through? • 4. Name where all 3 types of rocks are found (form). • 5. Fossils are found mainly in which type of rock.
Construct & Label a Transverse Wave • Show High Frequency • Low Frequency • One Wave Cycle • Amplitude • Resting Position • Wavelength • Crest • Trough