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Jump Start #1. A standing wave has areas that don’t leave the rest position. These are called. A – Nodes B – Crests C – Troughs D – Compression. Jump Start #1. 2) A transverse wave causes the medium to vibrate: A – Parallel to the direction the wave moves
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Jump Start #1 A standing wave has areas that don’t leave the rest position. These are called. A – Nodes B – Crests C – Troughs D – Compression
Jump Start #1 2) A transverse wave causes the medium to vibrate: A – Parallel to the direction the wave moves B – At right angles to the direction the wave travels C – Only in one direction D - Randomly
Jump Start #1 3) A longitudinal wave does not have crests and troughs like a transverse wave. A longitudinal wave has: A – Compression B – Surface C – Rarefaction D – Both A and C
Jump Start #1 4) A transverse wave is traveling along a slinky on a table. When that wave reaches the end of the slinky, which is being held still, the wave will: A – Reflect back in the opposite direction B – Lose energy and disappear C – Change into a longitudinal wave D – Increase in amplitude
Jump Start #1 5)Label the parts of the wave below using the following terms: Amplitude Crest Wavelength Trough
Jump Start #1 6) If a wave pulse on a slinky travels 10 meters in 2 seconds what is the speed of that wave? (speed = d/t) A – 10 m/s B – 5 m/s C – 12 m/s D – 20 m/s
Semester Overview Waves Electricity and Magnetism Motion and Forces Energy Work and Power
Waves What comes to mind? http://www.youtube.com/watch?v=Qf0t4qIVWF4&safety_mode=true&persist_safety_mode=1
Energy and Waves Mechanical Wave – when a source of energy causes a vibration to travel through a medium. What is a medium? Air Vortex Canon
Parts of a Wave • Medium • Crest • Trough • Compression • Rarefaction • Frequency • Period • Hertz • Wavelength • Speed • Amplitude • Mechanical Wave • Transverse Wave • Surface Wave
Breaking Sound Barrier • http://www.youtube.com/watch?v=7HbMcg-quwA • http://www.grc.nasa.gov/WWW/K-12/airplane/sndwave.html
How Fast Can Waves Travel? Speed of Sound 343 meters/second 1,125 feet/second 768 miles/hour WOW!!!
How Fast Can Waves Travel? Speed of Light 299,792,458 meters/second 186,000 miles per second 669,600,000 miles/hour That’s nearly 7 and ½ times around the equator of the earth in 1 second.
Wave Speed Speed = Wavelength X Frequency What is Frequency? The number of complete cycles in a given time. Frequency is measured in cycles per second or hertz (Hz)
Making Waves Use the string and a ruler to make waves with the following properties: • Wavelength = ½ meter
Making Waves Use the string and a ruler to make waves with the following properties: • Wavelength of 10 centimeters
Making Waves Use the string and a ruler to make waves with the following properties: • Amplitude of 20 centimeters
Making Waves Use the string and a ruler to make waves with the following properties: • Amplitude of 5 centimeters
Making Waves Use the string and a ruler to make waves with the following properties: • Wavelength = 25 centimeters and Amplitude of 10 centimeters