The document discusses the concept of resonance through examples such as bridges and mechanical systems. It explains that resonance occurs when an object vibrates at greater amplitudes due to another source emitting its natural frequency. Specifically, it discusses how the Tacoma Narrows Bridge collapsed in 1940 due to wind-induced oscillations resonating with the structure of the bridge. It also summarizes the collapse of the Nimitz Freeway in 1989, which was caused by an earthquake matching the bridge's resonant frequency. The document provides background on concepts like kinetic energy, potential energy, amplitude, and frequency to explain the physics of resonance.

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4. What You need to
Know
 Energy
o Kinetic Energy
o Potential Energy
 Amplitude
 Frequency

5. Resonance
- Resonance is defined as the tendency of an object to oscillate
or vibrate at greater amplitudes when another sources emits a
frequency of the object
- To explain it in clearer terms we take the example of a child
on a swing

6. Mismatched Frequency
What happens when the emitted
frequency is lower?
What happens when it’s higher?

8. Mismatched Frequency
What happens when the emitted
frequency is lower?
What happens when it’s higher?

9. - Mechanical Resonance is a type of resonance that deals
with mechanical systems.
- A mechanical system is taken to mean a physical object.
- Bridges and other large structures are the perfect
examples to demonstrate Mechanical resonance.

10. Nimitz Freeway
Collapse
- A bridge that was located in San Francisco, California
- Collapsed in 1989
- The reason for collapse was an earthquake that struck the
city.

11. Soldiers on
Bridge
- Great story my teacher always used to bring up in high
school.
- Now soldiers don’t march in step while crossing a bridge

12. So why did it collapse?

 One theory is that  Another theory is
it collapsed due that it collapsed
to forced due to self-
resonance excitation (aero-
elastic flutter)

13. The problem was with the design of the bridge
The bridge was closed from the sides, thus blocking
the air from passing through
Engineers were able to figure this out and so it was
decided that when building bridges, the sides would
be kept open

14. Works Cited

 Webdev17 (2009, March 2). Tacoma-Narrows Bridge construction & Collapse 1940 4 min.
Retrieved December 2, 2012. From:
http://www.youtube.com/watch?v=6AlSZT9k1ww
 GonzoNugent (2006, September 28). Tacoma Narrows Bridge Collapse “Gallopin Gertie”.
Retrieved December 2, 2012From: http://www.youtube.com/watch?v=j-zczJXSxnw
 Crowell Benjamin (2012). Light and Matter. n.d. n.d.pg 443-456. Retrieved from
http://www.lightandmatter.com/lm.pdf. Accessed on December 2, 2012. ( Statistical
data concerning Tacoma Narrows and Nimitz freeway was obtained from this
source)
 K. Billah and R. Scanlan (1991).
"Resonance, Tacoma Narrows Bridge Failure, and Undergraduate Physic Textbooks"
(PDF). American Journal of Physics 59 (2): 118 124.
http://www.ketchum.org/billah/Billah-Scanlan.pdf Retrieved December 2, 2012.
(Statistical data concerning Tacoma Narrows was obtained from this source)
 "Shattering wine glass." University of Salford Manchester. N.p., n.d. Web. 2 Dec.
2012. Retreived from
http://www.acoustics.salford.ac.uk/feschools/waves/wine1video.htm

15. Works Cited

 "0.jpg." article.wn.com. N.p., n.d. Web. 2 Dec. 2012.
<i.ytimg.com/vi/d6V2YAkyEdg/0.jpg>.
 "Amplitude." math.ubc.ca. N.p., n.d. Web. 2 Dec. 2012. www.math.ubc.ca
/~cass/courses/m309-03a/a1/pcheng/Amplitude.jpg.
 "Frequency." qrg.northwestern.edu. N.p., n.d. Web. 2 Dec. 2012.
www.qrg.northwestern.edu/projects/vss/docs/media/Communications/freq
uency.gif.
 "Nimitz_cypress_Structure."returntothe80s.wordpress.com. N.p., n.d. Web. 2 Dec.
2012. www.vias.org/physics/img/nimitz_Cypress_structure.jpg.
 "Potential-and-kinetic." Petervaldivia. N.p., n.d. Web. 2 Dec. 2012.
www.petervaldivia.com/technology/energy/image/potencial-and-
kinetic.bmp.
 "Tacoma Narrows Bridge (1940)."Wikipedia. N.p., n.d. Web. 2 Dec. 2012.
<en.wikipedia.org/wiki/File:Image-Tacoma_Narrows_Bridge1.gif>.
 "mum-girl-swing." oliverhume.com.au. N.p., n.d. Web. 2 Dec. 2012.
<www.oliverhume.com.au/assets/mum-girl-swing.jpg>.

16. Thanks for Watching!