Science Unit: School year: 2006/2007

Transcription

1 Science Unit: Lessn 4: Space Hw Ht and Hw Big? Schl year: 2006/2007 Develped fr: Develped by: Grade level: Duratin f lessn: Ntes: Sexsmith Elementary Schl, Vancuver Schl District Luana Avila (scientist), Jeanette Mumfrd and Mary Ctrell (teachers) Presented t grades 2 and 3, apprpriate fr grades 2-6 with age apprpriate mdificatins. 1 hur and 20 minutes Half f the lessn was delivered t tw classes tgether - the Star Size and Clur activity requires a large number f students. Objectives 1. Students will be able t recgnize that stars have different clurs 2. Students will be able t crrelate star clur with star brightness 3. Students will be able t crrelate star brightness with star size Backgrund Infrmatin Stars like humans cme in different sizes and clurs. Hwever, unlike peple a star s clur and brightness is highly dependent n its size. We can get clues abut hw ht a star is and a star s age frm a star s clur. Stars are ften classified based n size, temperature and spectra (r its clur). There are 7 main types f stars: O, B, A, F, G, K and M (easy mnemnic: Oh, be a fine girl, kiss me!). O and B stars are uncmmn but very bright and M stars are cmmn but dull. Astrnmers use a diagram (the Hertzsprung- Russell plt) t graph a star s clur, temperature, luminsity, spectral type, and evlutinary stage. The largest and brightest stars, the O, B and A stars are blue. F stars are blue t white. G stars are white t yellw. K stars are range t red and M stars are red. Our sun is a yellw star, which indicates that the sun is a medium-sized star. Rigel is a blue star. Rigel is lcated in the Orin cnstellatin, frming Orin s right ft, and it s an extremely large and bright star. Betelgeuse (prnunced beetle juice), which frms Orin s left shulder, is an example f a red star. Hwever, Betelgeuse is ne f the stars that escape the general rule f size and the amunt f heat a star prduces. Betelgeuse is a Red supergiant, these stars are extremely large but nt very ht. As a general rule, we culd say that blue stars are massive, bright, ht stars and red stars are small, dull, cl stars. The exceptins t this rule are Red Giants, which are cl but bright and massive in size. Space_Lessn 4 1

2 Vcabulary Predictin: Luminsity: Magnitude: An educated guess f the utcme f an experiment The ttal brightness f a star, the ttal amunt f energy a star radiates each secnd The measured brightness f a star, the amunt f energy we can see frm the Earth Materials fr this lessn Explring Stars DVD (see reference sectin f lessn) Blue tape White tape Star Chart wrksheet Yellw tape 2 Lighters Orange tape Red tape Vide Reprt wrksheet 2 Pasteur glass pipettes (if yu cannt find the pipets use paper clip wires) 1 timer (see ntes 1 and 3) In the Classrm Intrductry Discussin (Hk) 1. Review the material learned up t this lessn - make it a charades game. 2. Have the students watch the first tw sectins f the Explring Stars DVD the first sectin is abut the characteristics f stars and the secnd sectin reviews the lifecycle f a star. 3. Ask the students t write dwn n their vide reprt sheet any new facts they might learn frm the vide, as a well as any questins they might have. 4. Ask students t share with the class the new facts they learned, lead a discussin abut thse facts until they understand the crrelatin f size and the clur f a star. 5. Guide the students t crrelate the size with the amunt f gas bumping and its prductin f heat (learned in the last lessn), s they can assciate large stars with ht and bright stars. 6. When they understand that blue is htter than yellw d the Lighter Flame Clurs Experiment/Dem. Science Activity/Experiment Activity Title: Lighter Flames Clur Experiment/Dem Purpse f Activity: T shw hw blue stars are htter than yellw stars help crrelate clur and amunt f heat. Activity Instructins: 1. Shw the students tw lighter that are exactly the same mdel and tw glass pipettes. Explain that glass pipettes are made f very fine glass. 2. Light the lighters and hld in plain view f the students, ask them hw many clurs they see in the flame (blue and yellw) 3. Ask them what happens t fine glass when yu heat it it melts (in the case f a paper clip wire it becmes red) Space_Lessn 4 2

3 4. Ask them t predict what will happen t the glass pipettes when yu place them n the different clur flames the blue flame is in fact htter than the yellw flame, s the glass pipette placed in the blue flame shuld melt faster. Explain what a predictin means and that it is the way scientists learn abut everything in ur wrld. If yu have tw peple in the classrm have each persn light the lighter and bth will place the pipettes n the different flames at the same time. The persn with the pipette in the blue flame shuld gently supprt/press the tip f the pipette t the spark wheel such that when the pipette gets ht enugh it will bend easily creating an awe effect. The persn with the pipette n the yellw flame will nt be able t d the same thing because the yellw flame is much higher, thus farther away frm the spark wheel. It is nrmal fr the pipette n the yellw flame t g black, just wipe it with yur finger after the glass cls t shw the difference between the bent pipette and the straight ne. These pipettes are very easily brken, s be careful nt t apply t much pressure when supprting the tip n the spark wheel. NOTE 1: If yu are ding this activity as a dem and there is nly ne adult present, yu will nly be able t hld ne lighter and ne pipette (paper clip wire) at a time. Have ne f the students time yu with a timer r they culd simply cunt ut lud. NOTE 2: This activity was designed as a dem, but if the students are ld enugh just give a pair f students 2 lighters and 2 glass pipettes r 2 paper clips and let them cnduct the experiment and bservatins. NOTE 3: If yu are using paper clips it is als a gd idea t cunt hw lng it takes fr each t becme red. Thin metal clips will wrk better and if yu have access t a Bunsen burner r a prpane canister blw trch with a regulatr, it is better than using a lighter. Science Activity/Experiment Activity Title: Star Size and Clur Purpse f Activity: T shw that blue stars are bigger than red stars help crrelate star clur with star size. Activity Instructins: **This activity will wrk better if yu have at least 40 kids participating** 1. Fr 40 kids cut pieces f tape lng enugh t g n arund their arm: 30 pieces f blue tape (~80%) 4 pieces f white tape (~7%) 2 pieces f range tape (~5%) 1 piece f red tape (~2%) 3 pieces f yellw tape (~6%) Fr any ther number f kids just use the percentages t calculate the amunt f tape fr each clur. Just rund the numbers t the nearest integer. 2. Place ne piece f tape n each student and take them t an pen area where they wuld be able t run and play a tag game 3. Explain t the students that they are nt trying t run away frm peple but they are trying t find peple with the same clur tape as them. Once they fund smene they shuld hld hands and keep n seeking mre peple with the same clur tape. Space_Lessn 4 3

4 have fund their grup ask them t stp 4. When the majrity Have the blue grup with 30 children frm a large ring arund the smaller grups Have the smaller grups als frm rings Draw attentin t hw much bigger a blue star is cmpared t the ther clur stars 5. Take the students back t the classrm and give them the Star Chart wrksheet t fill ut The first clumn the students shuld draw the star and write the number f kids in that grup The secnd clumn they shuld clur the bx with the apprpriate clur, r just write the clur name The third clumn has a thermmeter that ges frm very ht t cl, frm tp t bttm. Students shuld calculate hw much bigger ne grup is cmpared t the ttal using fractins. Eg. The blue grup had 30 / 40 kids = 3/4, s 75% f the thermmeter shuld be clured blue frm the tp t the bttm. Then they had 10 / 40 kids left t be divided int 4 parts. The white grup had 4 kids / 10 kids left, s 40% f the leftver space shuld be clured white. If yur numbers are cmplicated, draw the bundary lines (based n the percentages given with the tapes) n the sheet and ask them t clur the thermmeter accrdingly. Scientific Reprt: the vide reprt wrksheet and the star chart wrksheet will be their scientific reprts fr this lessn. Clsure: Play a quick slightly altered Simn Says game divide the students int tw grups facing each ther: brightness and size. The teacher is the clur. When yu say a clur the grups will have t act accrdingly. Yu culd cme up with actins fr the intermediate clurs. Clur Size grup will d: Brightness grup will d: Blue Large Hld their arms and legs ut and inflate their cheeks t a maximum Jump up and dwn White Yellw Medium Hld their arms dwn and leave nt inflate their cheeks Stand up Orange Red Small Hld their arms and legs clse t their bdies and make a fish muth (suck in their cheeks) cruch References 1. Discvery Educatin. DiscverySchl.cm. Lessn Plans Library. Accessed April [Place t purchase the Explring stars DVD/Vide] 2. Surce f the Hertzsprung-Russell diagram n page 1 f this lessn. Space_Lessn 4 4

5 Teacher Assessment f Learning 1. D the students knw the pssible clurs f stars? 2. Are the students able t crrelate star clur and star size? 3. Are the students able t crrelate star clur and the amunt f heat a star prduces? 4. D the students understand that bigger stars are htter and therefre brighter? Extensin f Lessn Plan 1. This lessn can be mdified fr higher grades where the students are able t cnduct experiments using fire. 2. Using blue, white, yellw, range and red ballns ask the students t make a star f each clur. The ballns shuld be inflated in accrding t the size f each clur star. Then fr fun they culd decrate the ballns and tie it n a string in crescent rder f size. Space_Lessn 4 5

6 Name: Star Chart Star size Star clur Heat Very Ht Number f kids: Number f kids: Number f kids: Number f kids: Number f kids: Cl

7 Name: Date: Vide Reprt TITLE: FACTS I LEARNED: QUESTIONS I HAVE: ILLUSTRATIONS: Illustratins btained frm Discvery Schl's Clip Art Gallery created by Mark A. Hicks, illustratr