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Geography 2152F/G Lecture Notes - Lecture 1: Landfall, Coastal Erosion, Sea Level Rise

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kiroelboughdady

17 Feb 2022

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Western University

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Course

Geography 2152F/G

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Document Summary

Scientists observe a hazardous event and form a possible explanation for the cause. Data is then collected to test the hypothesis. Knowing the cause allows for the identification of where hazards may occur. Knowledge of past events aids in predicting future events. These events are natural forces; they only become hazardous when they disrupt human activity or the environment. These processes are not within our control; we cannot prevent them; we can only respond to them. The best solution to mitigate loss is preparation. Accurate predictions and forecasts are necessary to reduce loss. Prediction: a specific time, date, location, and magnitude of the event. Forecast: a range of probability for the event. For example, a hurricane making landfall can be predicted but an earthquake or a volcanic eruption can only be forecasted. Consequences: damage to people, property, the environment, the economy. Acceptable risk is the amount of risk that an individual is willing to take.

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Related Questions

This geometry task may be helpful for devising amathematicalprocedure for the next lab.

A right triangle has legs ofknown lengths 2L and h. Find thelength of the line segment x whichis parallel to side h. Explainyour reasoning. Image in weblinkbelow:

http://paer.rutgers.edu/194/Downloads/194LAB07.pdfRY4bB71082bfFuqzISDrWGDOWfNgGl208qJNQTAhpzWjb_ahDlhGHPLz19S1Eq95&q=cache%3AnpyQu9LlzykJ%3Apaer.rutgers.edu%2F194%2FDownloads%2F194LAB07.pdf%20this%20geometry%20task%20may%20be%20helpful%20for%20devising%20a%20mathematical%20procedure%20for%20the%20next%20lab.%20A%20right%20triangle&docid=5c8a26db354186a31ce6383

POSTSCRIPT: EFFECTS OFASSUMPTIONS

The marbled murrelet is asmall bird that lives in the PacificNorthwest where old-growthforests are close to the sea. It nests inthe forests and feedsoffshore. It is now highly endangeredthroughout its range, whichextends from Northern California toAlaska.

These birds are extremelyvulnerable to loss of their habitat,because they nest exclusivelyin the same old-growth coniferoustrees that are prime targets forlogging. Considerable efforts havebeen made to protect the speciesby restricting timber operations inthe areas in which they areknown to nest. Scientists predicted thatthe population should growback. However until recently naturalistswere puzzledand

dismayed because thepopulation of marbled murrelets did notseem to be recovering oreven stabilizing.

A recent study suggests thereason why this testing experimentin conservation did not confirmthe prediction. The scientistsoverlooked an important assumption:murrelets can also be threatenedby man's activity at sea.Overfishing has severely reduced thepopulation of small,energy-rich fish that murrelets rely upon formost of theircalories.

Climate change of uncertainorigin may have also disrupted thefood chain, and El Nino currentsmay have changed the distributionof the phytoplankton that formsthe base of all marine life.

Further efforts to preservethe marbled murrelet must be basedon accurate assumptions aboutthe origin of their difficulties.

Could naturalists have betterconsidered their originalassumptions years ago? What would yousay?

I have written my answers in for the one i may of understood!Any help would be great even explanation on how to dothe parts....PLEASE HELP THANK YOU!!!!!!!!!

B. One can purchase so-called Ceramic speakers which haveavibrating ceramic instead

of a coil-driven cone to produce sound waves. These arecapableof producing

frequencies well above the range of human hearing and, infactare used for sonar and

ultrasound applications. The disks used have aconductivecoating applied to either side

of the disk and the ceramic material reacts to anappliedvoltage by contracting or

expanding by an amount proportional to the voltage.Thesedevices are capacitive rather

than inductive.

1. Write the expression for the impedance of such a speakerinterms of the resistance

and capacitance.

2. Find an expression for the frequency Ï at whichtheresistance equals the reactance of

the ceramic speaker, in terms of R and C.

3. With R = 8Î© and C = .25Î¼F, calculate thefrequency Ï, withunits, that will give R =

4. Using Ïo for the frequency you calculated in 3,calculatethe total impedance, Z, for

the following frequencies and plot the results on the logplotprovided.

Ï/ Ïo 10-4 10-3 10-2 10-1 1 10 102 103 104

6. Locate your answer for part (2) on the plot. What featureofthe plot corresponds to

that answer? [4 points]

7. Describe how to quickly sketch this log-log plot for anRCcircuit with only one

calculation, based on your answer to (6). [5 points]

2 3 4 5 6 7 8 9 10

8. Using the same resistance of 8Î©, what value fortheinductance in an LR circuit would

give XL = 8Î© at the same Ïo value calculated in 3?

9. Using Ïo for the frequency you calculated in 3,calculatethe total impedance, Z, of the

LR circuit for the following frequencies and plot theresultson the log plot provided.

Ï/ Ïo 10-4 10-3 10-2 10-1 1 10 102 103 104

The emergence of line spectra from a gas when a current passesthrough it was an observed phenomenon waiting for an explanation inthe early 20th century. The atomic line spectra coming fromelements such as hydrogen had been analyzed since the late 19thcentury. By studying the wavelength of the emerging radiation ofhydrogen, experimenters found (often by trial and error) that thewavelengths in those spectra were described by the formula

\frac{1}{\lambda} = R \left( \frac{1}{n_1^2} - \frac{1}{n_2^2}\right),
where R is known as the Rydberg constant. It has a value of R =1.097 \times 10^{7}\; \rm m^{-1}. The variables n_1 and n_2 areinteger numbers (n_1 = 1,2,3,4,\dots). As experiments continued,scientists began to see more and more characteristic lines emergingfrom the hydrogen spectrum. Each of them corresponded to awavelength predicted by this formula with some integer values forn_1 and n_2.

In 1913, Niels Bohr provided an explanation for the observationsmade in experiments by proposing that each electron in an atom hadonly certain allowable energy levels. Furthermore, he postulatedthat when an electron changed its energy level, it must emit orabsorb a single photon with the energy equal to the energydifference between the two levels.

With this interpretation, the variables n_1 and n_2 acquired newsignificance. Bohr's model predicted that n_2 was the initialenergy state of the atom (n_initial) and that n_1 was the finalstate of the atom (n_final). A photon with the predicted wavelengthwas created when an atom made a transition from its initial energystate to a lower final energy state. The equation now read

\frac{1}{\lambda} = R \left( \frac{1}{n_{\rm final}^2} -\frac{1}{n_{\rm initial}^2} \right).
Bohr's model also predicted that a photon of the appropriatewavelength (given by the same formula) could promote an atom from alower energy level to a higher one.

In this problem, we explore the photon characteristics necessaryfor transitions between energy levels in hydrogen and singlyionized {\rm He}^+, whose energy levels are accurately predicted bythe Bohr model.
What is the change in energy DeltaE of the hydrogen atom as theelectron makes the transition from the n=3 energy level to the n=1energy level?
Express your answer numerically in electron volts.

b. When an atom makes a transition from a higher energy level to alower one, a photon is released. What is the wavelength of thephoton that is emitted from the atom during the transition from n=3to n=1?
Express your answer numerically in angstroms.

c.

When the hydrogen atom makes the transition from the n=2 to the n=1energy level, it emits a photon. This photon can be absorbed by toa singly ionized helium atom ({\rm He}^+) in its second energylevel (n_{\rm initial} = 2), causing it to move to a higher energylevel. To what final energy level number n_final can the photonpromote the helium ion?

Note that {\rm He}^+ has two protons in its nucleus and a singleelectron.
Express your answer as an integer.

Please answer fully, Thank you
a.