1 / 13

DO NOW

DO NOW. How many days are left until we reach our big goal? What type of wave has an up and down motion? What type of wave contains compressions? Is sound a transverse or longitudinal wave?. DO NOW REVIEW. How many days are left until we reach our big goal?

alda
Télécharger la présentation

DO NOW

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. DO NOW How many days are left until we reach our big goal? What type of wave has an up and down motion? What type of wave contains compressions? Is sound a transverse or longitudinal wave?

  2. DO NOW REVIEW How many days are left until we reach our big goal? What type of wave has an up and down motion? What type of wave contains compressions? Is sound a transverse or longitudinal wave? QUIZ AVERAGE! 1: 82% 2: 94% 3: 100% 5: 97% 6: 82% 7: 99%

  3. PROBLEM! CAN CELL PHONES CAUSE BRAIN CANCER?!

  4. HOW CAN WE FIND FREQUENCY? Things we decided we need to know: - Types of waves - What is “high frequency”? - What is a genetic mutation? Today we will: - Define wavelength, amplitude, and frequency - Use the equation v=w x f to find

  5. Parts of Waves - Transverse • The crest is the point where the medium has the most positive displacement • The trough is the point where the medium has the most negative displacement • The amplitude is the distance from middle to a crest or trough • A wavelength is the distance from one crest to the next crest • Or trough to trough

  6. Parts of a Wave – Longitudinal • A Compression is where the wave makes the medium most dense • A Rarefaction where the wave makes the medium least dense • In a longitudinal wave, awavelength is the distance from one compression to the next compression • Or rarefaction to rarefaction

  7. Labeling Practice

  8. But what about frequency? Frequency is the number of times something happens – measured in hertz (Hz) For waves its number of wavelengths that pass in one second

  9. The Equation Lambda

  10. Practice Problem #1 A Flute makes a sound wave in air where the speed of sound is 340 m/s. The sound wave has a wavelength of 50m. What is the frequency of the sound wave? GUESS METHOD!

  11. Practice Problem #2 A drummer in the band plays on a steel marimba. The sound waves travel through the steel with a frequency of 240 Hz and with a 2 m wavelength. What is the speed of the sound from the drum? A trumpeter makes a sound wave with a wavelength of 1.5 m. The sound travels through air where the speed of sound is 340 m/s. What is the frequency of the sound wave? GUESS METHOD!

  12. Practice Problem #3 A trumpeter makes a sound wave with a wavelength of 1.5 m. The sound travels through air where the speed of sound is 340 m/s. What is the frequency of the sound wave? GUESS METHOD!

  13. EXIT TICKET Which has a higher frequency: a wave with a speed of 15 m/s and a wavelength of 4m or a wave with a speed of 15 m/s and a wavelength of 2m? Label a crest, trough, wavelength, and amplitude

More Related