What would a coastal town would look like after few hours and few years?

Little change in few hours but shore line will wear off after years.

How does a ocean affect a coastal town?Page 128

Earth's History. All the processes that have been discussed require long periods of time to create a noticeable change on Earth's surface. You can just imagine how long it would take to create an oceanS as vast as the Pacific Ocean if the ocean floor moves only at about 10 cm/year. It is then important to know the history of Earth to learn the complexities of its past and be able to use it to understand the present. Just like learning the history of a country that requires one to read a lot of books, learning the history of Earth involves studying a lot of rocks. Rocks, especially sedimentary rocks, contain a lot of information about Earth's past. It holds the key to most of the geologic processes that happened on Earth and the key to uncovering how life on Earth evolved. But these discoveries are worthless if there is no time perspective. Thus, one of the most important contributions of geologists to mankind is the geologic time scale, which holds a history that is exceedingly long.The geologic time scale divides the history of Earth into different blocks of time by using relative dating. Since geologists use rocks to understand Earth's history, dating does not give accurate numerical dates, it only tells that an event preceded the relative dating places these rocks in their proper sequence of formation. But relative other. This method is still widely used today, alongside a more accurate method called absolute dating, which uses radioactive elements. With relative and absolute dating. geologists can trace the history of Earth. Relative Dating. Relative dating requires one to know the basic principles such as law of super-position, principle of original horizontality, principle of cross-cutting relationships, and unconformities.Law of Superposition The law of superposition is the most basic principle in relative dating. It states that in an undeformed sequence of sedimentary rock, the layers found at the top are the youngest rocks and the layers at the bottom are the oldest. It may seem too obvious, but this principle has only been clearly stated in 1669 by the Danish anatomist, geologist, and priest, Nicolaus Steno. Principle of Original Horizontality Along with the law of superposition, Steno stated that an undeformed sequence is the one where the layers are still in a horizontal position. This follows the principle of original horizontality, which states that sediments are deposited horizontally. Principle of Cross-Cutting Relationships The principle of cross-cutting relationships determines which events occurred first depending on which rocks are affected. The geologic layer that cuts another is younger than the layer it cuts across.Unconformities Rock layers that have not been interrupted are considered conformable. These sites represent spans of geologic time. But there is no place on Earth that has a complete conformable stratum since external and internal processes have always interrupted the deposition of the sediments. These breaks in the record of the rock strata are called unconformities. Using unconformities, geologic events are determined. There are three basic types of unconformities angular unconformity, disconformity, and nonconformity. Angular unconformity is characterized by having tilted or folded sedimentary rocks below younger, horizontal layers of rock. Disconformity is determined where there are missing parallel rock layers. Erosion takes place and removes the younger top layers and then deposition would once again happen. Nonconformity is characterized by an igneous or metamorphic rock found below a sedimentary rock. Figure 3-13. Three basic types of unconformities Using these principles for relative dating, one can determine the order of events However, relative dating does not give a time element as to when they happened. Absolute Dating For a much more accurate method of determining the history of Earth, geologists make use of absolute dating. This method uses unstable elements to determine the exact age of rocks. Isotopes are elements that have the same number of protons but different number of neutrons. Most isotopes are stable but some may be unstable. This is because the forces that bind the protons and neutrons in the nucleus of the isotope are not strong enough to hold them together, resulting in a radioactive decay, The unstable isotopes are called radioactive isotopes or parent isotopes. When these parent isotopes undergo radioactive decay, new isotopes, known as daughter products, are formed. The time it takes for one-half of the nuclei in the sample to decay is called half-life. This amount of time is fixed for each kind of radioactive isotope no matter what physical conditions it is subjected to. The ratio of parent daughter isotope determines how many half-lives have passed. If it is 1:1, then one half-life has passed; if it is 1:3, then two half-lives have passed; and if 1:7, then three half-lives have passed, and so on. Therefore, using the concept of half-life and parent-daughter ratio, geologists can determine the exact age of the sample. This method is called radiometric dating. It uses five radioactive isotopes to determine the age of rocks. For dating rocks that are about a million years old, rubidium-87, thorium-232, and the two isotopes of uranium (U-238 and U-235) are used. The fifth radioactive isotope is potassium-40, which has a half-life of 1.3 billion years. With these radioactive elements, determining the accurate age of rocks becomes easier. For dating events that are more recent, radiocarbon dating is used. This method uses carbon-14. Carbon-14 has a half-life of 5730 years and can be used to date back events up to 75000 years. All organisms contain a small amount of carbon-14, which is proportional with the amount of carbon-12. When an organism dies, the carbon-14 decays and is no longer replaced. The amount of carbon-14 left in the sample is then compared to the amounts of carbon-12 present, and radiocarbon dates can then be determined. This method has been particularly useful for anthropologists, archeologists, historians, and geologists for events that are much more recent.Fossils Aside from rocks, geologists also use the remains of living organisms in understanding Earth's history. Some fossils are formed from parts of an organism (body fossil), while some provide signs or clues as to which life-forms were present at that time (Frace fossils). Fossils contain a lot of information about the past the kind of organisms that have lived, the environment where organisms lived, and the evolution organisms underwent as their environment changed. However, not all organisms turned into fossils, therefore, scientists cannot learn everything about the past using fossils alone. There are also fossils that are used to determine the age of a rock. These are index fossils and these are only found in rocks of a particular age. The organisms that turned into index fossils have a relatively short life-spanning from a few million years to a few hundred million years. Index fossils are also found in most of the common rocks around the world, which makes them easier to identify.The methods used for dating the age of rocks are also used for fossils. Absolute dating is more commonly used since it can give exact numerical dates for the age, but relative dating can also be used to determine which fossils are older.

What is an earthquake? Would you be surprised to learn that several million earthquakes happen every year? Seriously. Most are so small in magnitude or size that we cannot even feel them. In fact, only 20 earthquakes are efficiently reported each year in the United States Geological Survey. Wow! That is a huge difference! The Earth has four major layers. Inner core, outer core, mantle, and crust. Think of the crust and top of the mantle like the skin of the earth. This skin is made up of different pieces of rock called tectonic plates. There are about 15 major slabs that join together, kind of like a puzzle. The edges around the tectonic plates are called plate boundaries. These massive pieces of rock slide back and forth under the Earth's surface, bumping up against each other and creating a lot of tension. This tension and movement create faults, which are basically huge cracks in the rock. When the faults get stuck, they build up pressure. And when they get unstuck, you guessed it, an earthquake. So basically, an earthquake is caused by the shifting and sliding of tectonic plates on the Earth's upper mantle and crust. There are three ways that tectonic plates shift or slide. They are subduction, lateral sliding, and spreading. Subduction happens when plates crash into each other. This can cause one plate to slide under another and be destroyed. Or the edges of the plate may rise up and form mountains. Lateral sliding means that the plates slide alongside each other, which can create lots of friction. And like you might have guessed, spreading happens when plates move apart from each other. When they do, melted rock between the plates rises and cools, forming new crust. Here's an interesting fact. Nearly 90% of all earthquakes begin in the Pacific Ocean, in an area called the Ring of Fire. It's called the Ring of Fire because along with earthquakes, it's filled with many active volcanoes. More than 450! Earthquakes can be powerful enough to change the surface of the earth and can do a lot of damage. And sometimes earthquakes can even cause other natural disasters, like avalanches, landslides, and tsunamis. Pretty wild, right? The epicenter is the location of an earthquake on the Earth's surface. The closer you are to the epicenter, the more of the earthquake you will feel. Earthquakes lose intensity as they travel away from the epicenter. Scientists measure the intensity of an earthquake using a special device called a seismograph. Seismometers detect and measure the vibrations given off by an earthquake. Magnitude is the number given to record the size of an earthquake. For example, a magnitude 5.5 is considered moderate. Above 8.0 is considered a major earthquake and we see one every year or two. Earthquakes measured at 2.5 or less are usually not felt, but can be recorded. And believe it or not, there are millions that happen each year. You can make a model of a seismograph at home, and we are going to show you how. It's activity time! You can print off directions for this one on our website at learnbright.org. You'll need a cardboard box, string, a plastic cup, a marker, small heavy objects, a long strip of paper, and a friend because this is an activity for at least two people. Now comes the fun part. One friend shakes the box, alternating between hard and soft and slow and fast, while the other friend is pulling the strip of paper through the bottom. Watch the marker as it records the movement. This is exactly what a seismograph does during an earthquake. So, in a way, we have not only created our own seismograph, but our own earthquake as well. Now, we can analyze the data just like scientists. Can you tell how hard the box was shaking based on the line? Can you tell when it was barely shaking at all? You are on your way to becoming a seismologist. A seismologist is a person that studies earthquakes. It's pretty cool to watch the process, but it's even more exciting to do it yourself. You can head on over to our website to get detailed instructions for this activity. Just download the lesson plan and as always have fun! Hope you had fun learning with us! Visit us at learnbright.org for thousands of Hope you had fun learning with us! Visit us at learnbright.org for thousands of free resources and turnkey solutions for teachers and homeschoolers.

Eff..rs of ott.-PoFllat i What woLrld hoppen ro our colnrry i, it is ovetsp.pulored? When our counrry is ov€.-populdted, re @ €xp€ri.nce rh€ foll.wirg: Food is our bdsic h@d. Wh€n th€.Cs an ih.re.se ir populdtion it neans thar hore ,@d is iealed. It rheds ho .naJgh food, rrtrple irll srruggle wirh eddr oth€r in ordeLro €!'r- As o l!fllr, lhde rill be o f@d -- , ond ou, now]nert of on ihdiyiduol fron d c..tair - the move$eni o, on individudl our of o cerrain pla.e which help r€duce ihe populotion of th6t fr Arcih€. b.sic ned is w.ra. Wde. shorroge ocu.s when there is on ircreare of hu,nber of p@ple ro be $pptied. rn owr-popur.t d ore.s, woler is rdior€d, Ir rEB rhoi supplies like ti,tWSS ond ,IWSI can'i $pply enoish worer. Do you hdve enough supply of sai.. in your oreo? Aside f.om food alld worer, shelier is olso ohe o, our inportant heeds. As the populoiion ihcre.!e!, building n.w hoLr!€s or rhelt€r is limit.i. To find solulion to this prcbl€n, some goverihent og.ncies dnd orhs non{ov€Ihrehl offi.iofs (N6O) .onvefied sot@ ti.elields, du,np site. dnd nountcirlr inlo flbdivisions dnd relidentiols. Sut whot uould be ths effect o{ coMrtiig .i@fields to .6id€nri6l uits in our food supply? z , 2 Z Z :'", becouse there ore no enough space for prcpex garbage dkposol. ^s o r€sulr, sore peoPle lend to ihrow'their gorbdge onywh.f€. oorbdge baones brc{niry ond rursing ground of iEecrs and onidols ihot @se horm ro pe.ple. Dec.yiry garboge olso produces r,hpleaiant odor ard ehen burn if pmduces pois.nour qds @lled nelhohe As ihe populdtion incr€a3*, the 9d6.9e dso incraes. nris is T't ,,8 T H Wha you de living in on oa-populdi.d pla@, you moy oqaiae halrh prcblerns. Ir is be@@. the woi.r srpply is limit.d ihct will l..d you to poor hygi.ni. hobirs. In plo.4 like rhis, the surrouhdiigs naybe uniidy. o focrorthoi @uld oko cfFe.t your h4l'th. The common oilments rhot yd @uld oc$rire in ovesfDpllar€d ploces ore bEnchil is, o5l hnq. diqrrha and rube.culosis. 7,\ ,\\ \1" 6. Lnck of Herlrh sarvice llosi Pelple in 6n oM-populci€d 6ra 90 ro rubli. heilrh @trtas ond governhent hospirols be6u.e ii prcvides fr@ @Eulrorion oid los @sr rEdicdrions. A3 a ..suli, lh€s€ gow.nnenr dg€rciB b.@ne itud.4$re in mcetiig ihe n eds b..ou!€ df ihsrffici€nr funds. Lock of medicol personnel ,o odmaiisi€I is also s problen in mosr hosptols ev€n rhere or. od.audtc supply of hedicire!. 7_ Do you how wlry rhe crim€ roi€ hexs ih becdur€ fiDre pe.ple o.e fnJrrct€d d@ ro sLffici€.i naE io supp.rr their forniliG. ouf country inclY{ses? If is uh.mploym€ni dnd hdve no arinet .re u$dv gr€{rer ia dn dq-popltdled ra whq. tl, , a, v, tlr I E. Air ard Wat€r Pollutioh How dir be.o'nes pollut€d? I11€ dir b@'n€s p.llurn be.4ne of rhe hormfolgoees thot ser. produ.4 by the fdciori€s and vehicles. Itete {octories ond whi.l6 @ fuel ro run nochiB ond .JBin6. In ,h€ prc.ess, they give our Cdrboh Dioxide ond other ho.6ful gars.r such 6 Nittugei Oxide, Corbon l oioxide dnd Le.d iiio the oir. Do you know whot .ontdbute io ihe incr€asing number of whides qnd foctories? It is ihe inc.6e o, populdtion. As whdt I hove dis.!sse!, wirh a lihired sra.e 9@bd9e disposalie one of the problens thot .o!ld ise i, dh o!er-pop!,.t€d ploce. exn,jple ot thie orc rhos€ pelpl€ livi,rg oh the raverside teid 'ro ,hrou, lheir gEr&ge Hde you seen 'th. P6si9 river or the Tulyahan river? Did you {ind it Whdr do you think i! ihe eff€.t of ihis ih the.re4iures sho lives ih Ahothd f6do.s thal could.on rlbule to wdtd pollutioh dre oil s?ills, gorbqg€ fro,n boa, or ships ahd som€ ihdust.iol wosre. 9. Ite l@96f p4.enroge group. Individuols who orc this grclp. of olr popllarioh is compos.n of the working @pobla of s'rpporting ,heir fomilies nok !-up Though rhas group hol& the lojgeei percenroge of d. populaiion, rhis olso becomer one o{ oveFpopulored probl€]ns b€4use there ore rc jobs awildble fo. oll of iha10. Erergy Shortdge ltere will be on energy shortdge iJ ihe populdtion incre63"l be.dise rhe d.,nand i. €le.iriciry is high. Why is thai wh.n th. PoPqldion inclE.g, rhe d4ord in el4tricity is high? Ir B be.ouse there $,ould be 8to.e hdsat dnd blildirys to lighr ond nore el?riric oPPliohces ro run. rt.6rcznho!3.Ef+ed Whor is rhe grernho@ eff€.r? In whoi say il c.uld offect c2 6re.hhG. effed is rhe wdrniltg of rhe drltlosphee. lvhen the 5un worft rhe.nrrh s1jrf.@, sone of rhe h@r go€J bo.k ro rhe ornos?herc. Air an the dtnDsphere which is C@boi Dioxid. ,rops ihe heot 6hd it mok6 the a.th very worm. As ihe populdtion coniinuou!|,l gtol4 , the gt@rl$use etfe.t b@res no.e visible. Ir is becaosu ,hera ore mo.e focrories snd whicl.s iha, produce wdst€s ond fuma5 which cduses more C{.bo. Diodde ir the ormosphere. As a rcsutt, ,herc eiould be nore h4, ,rop in the ornosphere uhich osk6 th. @ih nuch wornerIf this will hoppen continuously, ,h€ fish ih th€ ocah *ill di€, ricerields/f@mlands will dry too due to lh€ wcm clitnole 12. Destruction of rhe Ozone Loyer A5 whot you hove l@med lrheh you de in v5-6, rhot the qzore ldver is 'the proiecrive loy€. of the olnosPhd€. ft protects us {rom the homful effects of ultrdviolei rays of the su. Do you khow ,hot our Ozore lol€t q4. dQ4tt\!ci.d? Il olreadY hod holes lhai dllow the ulrroviolet rdys to .4dt ihe @rrh. How do6 this hdpPei? Does th. in rc$e of poPuldioh h@€ sonething 'to do tr,lh ir? Yes, rhe I6i grov/irts PoPuldiion .odribuied o lot be@use 6 th' populotion incre3es, rhe u5e of refrigerd'tors, d€rosol lProvs 6nd pl4srics 6bo ihcre&s6. The sid producls coiiojn chemicol called Chlorofluorocdrbons (CFCS) which is mix wafh ihe dir in ihe ormosPher€. As o resulr. ihe hcrmfirl chernicol r€oches the Prolectiw ldver dnd lhrowh. hole in {hid ult@iolzi cahders aid cai4.ct3 ,F.*Y.iis hi!586$q€9.7,- Ho$ doas dcid rdin form? Is cid roii hdmful ro rEn? In the prcvious dis.ussions, yodt€ t.on€d rhd more vel .1e3 dnd fdctori€s or€ necded fo het the iii:.e.siry number o{ P@Pla. Lefs now fihd af hd f@tot.i€s dnd vehicle! .ontribure in the forrEtion of ocid When foctories 6nd whi.ler give off woste gd..3 ,hot will ,nix on lhe noisture i. rhe oir, it will ihen Produ.e sulPhu.i. ocld dnd Nitri. o.id. 'Ihe clol,Jd folb will ,h€h obsorb rhese ccids ond ehei ihe clold f.lls os .oin, ih. ccid is ahady Pdrr of itU/ha d.id ftin falls oh lok"!, ,46 or ocan ih€ fish sill die d.d if h fdlls oh fopnlonds,lhe pldni. together oith the soil B desrroyed. When you inhole dir with Niiric acid, your blood will los. irs @pobilily io fonspori Oxyg€h to your diff€.ai bodY Po.i3. ScieniisB include other rorns oJ dcidic pr€cipiigrion. Thes€ drc nisi, Do you krcw ihot Nuclerr power slotionr Use .adiodctive ,ndie.ials in producirE fuels, yet, rhey do and those .odioactiw rndlqlotE gi\e otf radio'ting en.rgy thoi is harmrul 'to livirq thilEs. wlren rodiotion enlert ihe body ot living things it {ill srq rhere for o lorg ,eriod of ri'ne. Exonple fhe rodiqtion vG srilled to the c.m. Then rhe @rn will be aie by rhe chicken, the .odiotion o the c.rn 'rill also 'tronsf€r to the chi.k€n. Wha on individuol als ihe nat of the chickeh sith mdiarion, helshe rill .ko oblorb ihe rodi@.tirc mtaid that will destrcy hB/her .€lls ond ruket hnn/hd si.r. Over-populoiion .on leld to food shoridg€, wdter shorroqe, housiB probl€ms, qdrbog€ probl€rs, lock of halrh sdi.e. tisa ol clit@ rote, oir ond woi€r pollution, uhanpl6ynat, eiergy 5horr69e, grenhoq3€ efreci, desrruction o( th. ozo@ lat/e?, rci.l roi. olld e.l€d. watta

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How does a nomad child go to class every day, though? A new idea is the travelling school, a big ger which goes where the herders go in the warmer months. These are the months when nomad parents really need their children's help. Mongolia is developing. There are more jobs now, and new towns. The travelling school allows Mongolian nomads to keep their traditional lifestyle, but learn about the modern world, too. The nomads hope their children can be part of both. Most people nowadays live in cities and towns crowded with people in towering skyscrapers or blocks of flats and heavy traffic on the streets. There are schools, shopping centres, cinemas, theatres and restaurants. The life of a Mongolian nomad couldn't be more different. B A family's nearest neighbours are kilometres away and the only building is the ger, their traditional tent. But it is thanks to their animals that these nomads manage to survive. Their horses carry them and their equipment over long distances. Their cows, yaks, goats and sheep give them food, wool and leather. The herder goes where the animals go, moving to find new grass. It's a hard life. The nomads' skin is dark and tough from the sun and wind, and their eyes are narrow to protect them from the harsh winter. If it gets too cold, there isn't enough to eat and they lose many animals. Nomads are proud to be herders and proud to live more freely than city people. They want their children to have an easier life, however, and try to send them to school.

Unit 5 (Photosynthesis) - EQ2 How does a chemical equation represent a chemical reaction?

A Clown Face How does a clown put on a face? Where does she start? First, she puts on white face paint. What comes next? How does a clown put on a face? Next, she puts paint around her mouth. She paints a big, red smile. What is next? How does a clown put on her face? Next, she paints her eyelids. What does she put on next? How does a clown put on her face? Next, she puts on big, fuzzy eyebrows. What comes after that? Then she paints big, pink circles on her cheeks. What comes next? How does a clown put on her face? Next, she puts on her red nose. It honks if you squeeze it. What does she do next? How does a clown put on her face? After putting on a red nose, she puts on a silly wig. What does she do next? Then she gets dressed. She puts on a polka-dot jacket and striped pants. And she puts on big, floppy shoes. At last the clown leaves the dressing room. Now it's time to make kids laugh.

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