1 / 22

Bell Work: Goal Setting

Bell Work: Goal Setting. Locate your goal sheet from January. Pick up a new goal sheet by the basket. Fill in your area averages on the goal sheet from the orange sheet. Fill out the rest of the goal sheet. Remember to choose specific and realistic things to do to improve your grade.

fontaine
Télécharger la présentation

Bell Work: Goal Setting

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Bell Work: Goal Setting • Locate your goal sheet from January. • Pick up a new goal sheet by the basket. • Fill in your area averages on the goal sheet from the orange sheet. • Fill out the rest of the goal sheet. Remember to choose specific and realistic things to do to improve your grade. Ex: Do review sheet as a practice test; review bell work 2x a week; study with a partner for 30 minutes; answer all lab questions; turn in on time

  2. Vibrations and Waves

  3. Waves carry energy from one place to another • Waves temporarily disrupt the medium through which they travel

  4. Energy is transmitted (moved) – matter is NOT transmitted • Two categories: mechanical and electromagnetic

  5. Electromagnetic Waves • do not need matter • perpendicular electric and magnetic fields • Radio, microwave, infrared (heat), visible light, ultraviolet, x-ray, gamma ray

  6. Mechanical Waves • need matter to travel • Cannot travel through a vacuum

  7. Longitudinal Waves • AKA compressional waves • matter vibrates same direction as the wave moves (parallel) • Examples: Sound is created from vibrating objects; AC current

  8. Transverse Waves • matter moves at a right angle to the movement of energy (perpendicular) • Examples: guitar string, stadium waves • video Practice

  9. Surface Waves • Surface wave: mixture of both Longitudinal and Transverse; matter travels in circles • Example: water waves

  10. Wave Speed • SPEED DEPENDS ONLY ON THE MEDIUM • Medium is the stuff that the wave travels through – spring, space, air, iron, 55o F water, etc.

  11. Wave Speed • Sound waves move at 343 m/s in room temperature air, faster in liquids and solids • Electromagnetic waves travel at speed of light c = 3 x 108 m/s; slower through matter

  12. Transverse WaveAnatomy crest crest amplitude Matter moves wavelength Rest line Energy moves trough λ trough Practice

  13. Bell Work: Which wave? • Which wave has the. . . • 1. . . most energy? • . . smallest • wavelength? • . . . . . smallest • frequency? • 4. . . . . smallest amplitude? • Which two waves have the same. . . .5. . . . . .amplitude? • 6. . . . . wavelength? A B C D

  14. Wave Properties Measuring Wave Properties

  15. Wave Relationships • as wavelength increases, frequency decreases (inversely related) • As wavelength increases, period increases (directly related) • As frequency increases, period decreases (inversely related) • Speed only depends on the medium that a wave travels through • Energy is shown in the amplitude

  16. If a water wave oscillated up and down three times each second and the distance between wave crest is 2 m, what is its frequency? Answer: 3 Hz What is its period? Answer: 1/3 second What is its wavelength? Answer: 2 m What is its wave speed? Answer: 6 m/s

  17. Shock Wave http://observe.phy.sfasu.edu/courses/phy101/lectures101/

  18. Sonic Booms • http://www.physics.sfasu.edu/astro/courses/phy101/SonicBoom.html

  19. What determines the speed of a wave? (a) the frequency (b) the wavelength (c) the amplitude (d) the period (e) the medium of transmission

  20. What dictates the frequency of a sound wave? (a) wavelength (b) medium (c) source of the sound (d) speed (e) amplitude

  21. Examples of Resonance • mass on a spring at resonance • swinging your legs in a swing • breaking a wine glass using sound • a singing rod caused by forced vibration • fog horn • a tuning fork exciting a guitar string • In 1940, the Tacoma Narrows Bridge was destroyed by wind-generated resonance.

  22. Tacoma Narrows Bridge Resonance allows energy to be transferred to a vibrating object efficiently if the energy is delivered at the natural frequency of vibration.

More Related