c v Activity: Investigating the Properties of Light Homework speed of light in vacuum speed of light in medium index of refraction of material

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We use fibre optics systems trnsmit telephone nd Internet communictions. A single opticl fibre cn be s thin s humn h, yet trnsmit thousnds of different signls t sme time (Figure 11.28).

A typicl opticl fibre cble cn be mde from thousnds of opticl fibres tightly pcked ger. Activity: D17 - Observing Refrction (pg. 435) Figure 11.28 A single opticl fibre cn fit through eye of needle.

29 Step 3 Refrction 1. Insert pencil glss of. Observe glss from side t vrious ngles. Record your observtions using lbelled digrms. Unit #3 Questions 5. Describe pth of from 2.

Keep wtching coin while you lower your eye: of your hed until coin just disppers () in step 3 (plurl:height medi) is mteril tht is being used or is undergoing from view behind rim of lid (Figure in

1 We use fibre optics systems trnsmit telephone nd Internet communictions. A single opticl fibre cn be s thin s humn h, yet trnsmit thousnds of different signls t sme time (Figure 11.28). This is becuse ech signl is sent t different wvelength through sme cble. Just s two flsh bems cn cross ech or nd n continue on ir wy unffected, thousnds of bems cn pss through sme cble. A typicl opticl fibre cble cn be mde from thousnds of opticl fibres tightly pcked ger. Activity: D17 - Observing Refrction (pg. 435) Figure A single opticl fibre cn fit through eye of needle. D17 Quick Lb Observing Refrction Pge 436 Purpose To observe wher bending of ffects wy we see certin objects Mterils & Equipment glss of pencil jr lid with opque rim coin Procedure Figure Step 3 Refrction 1. Insert pencil glss of. Observe glss from side t vrious ngles. Record your observtions using lbelled digrms. Unit #3 Questions 5. Describe pth of from 2. Plce jr lid with n opquein rim on desk nd lines, Although trvels stright. it bends when it psses from put coin in middle. 6. Drw ry digrm of rys from coin one nor, such s from. A 3. Keep wtching coin while you lower your eye: of your hed until coin just disppers () in step 3 (plurl:height medi) is mteril tht is being used or is undergoing from view behind rim of lid (Figure in step ). process. bending of rys s7. y pss between two different Compre your drwings in question 6 with those 4. Keeping your hed t sme level, pour done by clssmtes. lid, on p of coin. Observe.Refrction Record medi isclled refrction. cuses some very interesting your observtions using lbelled digrms. () How re your drwings similr? visul effects. For exmple, hndle of spoon in Figure How re your drwings different? ppers be broken t level of p of. When Pge 436 from spoon psses from, rys re Ry digrms model behviour of in mirrors nd lenses. 435 bent. Refrction is more thn just n opticl curiosity. It is used in designing nd building cmer lenses, eyeglsses, nd telescopes. Refrction is due chnges in speed of. For exmple, s moves from, its speed decreses. Different medi Figure spoon ppers be broken becuse rys chnge slow down by different mounts. more tht slows down, direction s y move from more is refrcted. nd from. You my hve sod beside pool or lke nd seen something on botm tht you wnted pick up. Yet, when you dove in, object not ws Pge 437where it ppered be. This is becuse rys chnged direction t surfce of s y pssed between nd Although trvels in stright lines, it bends when it. psses from Figure shows rys moving from nd one nor, such s from. A bending it psses fromweone refrcting s when y leve. When view refrcted rys, we ssume (plurl: medi) is mteril tht is being used or is undergoing y hve trvelled in stright line. If you trce nor rys tht rech eyes bck in stright line, you will find tht process. bending of rys s y pss between two different y do not led which chest. Insted, from chest in deep A ry of is electromgnetic rdition, cuse byinteresting chnge in speed of medi is clled refrction. Refrctioniscuses some very coming from shllower. trnsmitted in wves. ppers prticles in be Refrction of Light Refrction Refrction Pge 439 visul effects. For exmple, hndleslow of in offigure downspoon pssge wves, which results in b slowly through block of glss, During ppers be broken t levelreding of ptrvelling of more. When for exmple, thn it trvels through vcuum. from spoon psses from of, rys Purpose n effects of chnges in speedre of cn be seen in Figure ry strikes bent. Refrction is moreillustrtion thn just n opticl curiosity. It is used in How Light Refrcts Plexigls Stte pic nd purpose for t n ngle. As enters Plexigls, surfce You cn picture bem of s leding designing edge of wve, s nd building cmer lenses, eyeglsses, nd telescopes. slows illustrtions on se it nd down nd refrcts (). When leves shown in Figure At first, ll wves re prllel. n, Plexigls nd enters, it speeds up nd imge of chest Refrction is due chnges in speed of. For exmple, s wves re compressed s y enter nd slow down. If following pges in this section. Find refrcts gin tht does not refrct strikes surfce of t n ngle, tht prt of words in its cption tht lso occur. Notice moves from, speed decreses. Different medi Figure spoon ppers bem tht enters first will slow down first. Notice in digrm chests it enters nd n leves this block inside block. Light refrcts only t boundry Figure Lightctul refrcts in text. Write sttement bout this chnges direction of wves nd lso direction of be brokentht becuse rys chnge of Plexigls. when it is entering or leving. This slow down by different tht slows down, how mounts. illustrtion helps you more ry of. It is like line of skters chnging direction becuse direction s y move from Figure under chest ppers be higher thn it relly is. phogrph lso shows tht refrction is reversible skters t one end slow down on rough ice (Figure 11.34). understnd concept or ide. more is refrcted. nd from. process, in tht ngle of refrction entering block is exctly Figure Light cn be represented s series of wves tht You my hvecompress sod beside pool or lkesnd seen something on reversed leves block. ry immeditely speeds nd chnge direction s in,speed of Light y enter on n ngle. up gin s it leves botm tht you wnted pick up. Yet, when you doveblock. object A B C D E In vcuum of spce, where re re very few prticles, trvels ws not where it ppered be. This is becuse rys chnged t lmost 300 million m/s or m/s. Moving t this speed, Indexbetween of Refrction direction t surfce of s y pssed could trvel sevennd times round Erth in one second. However, just mount by which trnsprent decreses speed rough. Figure shows rys moving from trying nd move from clss clss when hllwys re like student of is indicted by number clled index of refrction, it is impossible for move t p speed when prticles get in Inquiry Activity on pge. 444 refrcting s yd18leve When full, refrcted lso we clledview refrctive index. lrger refrctive index, wy. speed of. more decreses rys, we ssume y hve trvelled in stright line. If you trce Figure Skter E slows down, mking entire row of skters turn. Light trvels fstest in vcuum. refrctive index of Tble 11.5 Index of Refrction for rys tht rech eyes bck in Light stright line, you will find tht Selected Medi of in vcuum is ssigned vlue of A vlue of UNIT D speed nd Geometric Optics 436 ngles of refrcted rys re usully mesured from 1.00 cn lso from be used for, since fourth deciml plce does y do not led chest. Insted, chest in deep Medi Index of Refrction, drwn t 9 surfce where ry crosses between not ffect clcultions bsed on Tble Since, glss, vcuum 1.00 (exctly) two medi. When trvels from, with low refrctive index, be coming from shllower. ppers dimond, nd or medi ll slow down, y hve higher Speed of Light Index of Refrction, with higher refrctive index, it bendsm/s wrd or. 300 million When trvels from denser During 3.0 Reding (higher 108refrctive m/s.index) less opticlly dense (lower refrctive index), it bends wy from. ngle of incidence, θi, nd ngle of refrction, θr, re mesured from. Figure Stte pic nd purpose for shows ngle of incidence, ngle θr, s θi, nd illustrtions on se ndof refrction, refrcts moving from () following pges in this section. Find glss, nd from glss. ofspeed chnges Purpose n Illustrtion due prticles of mtter getting in wy words Vcuum in cption tht lso occur in text. Write sttement bout how illustrtion helps you understnd concept or ide. vlues thn. refrctive index of, n, is determined by compring speed of in, v, with speed of in vcuum, c. This leds following definition: θi mount by which trnsprent decreses of speed speed of in vcuum θr index of refrction of mteril = speed of in c surfce or n = v glss () θr lrger refrctive index, more Since units cncel, refrctive index vlue does not hve imge of chest decreses speed of ny units. θi Figure Light moves () from glss nd from glss. ctul chest crbon dioxide gs lcohol 1.36 Pyrex glss 1.47 Plexigls 1.49 tble slt 1.51 flint glss 1.61 spphire 1.77 cubic zirconi 2.16 dimond 2.42 gllium phosphide 3.50 Figure under chest ppers be higher thn it relly is. Ry digrms model behviour of in mirrors nd lenses. 439 Speed of Light Ry digrms model behviour of in mirrors nd lenses. In vcuum of spce, where re re very few prticles, trvels 8 437

2 index of refrction of mteril = speed of in vcuum speed of in Exmple: n = c v speed of in smple of glss is m/s. speed of in vcuum is m/ s. Wht is refrctive index of this glss? Homework Activity: Investigting Properties of Light Chpter 11.1 Review: pg 433 Qu #1, 3, 4, 8, 11, 12, 15, 18 Red pg pg 438 #1 nd 3 for both groups Hndout b R i r

Pge 439 Activity: Investigting Refrction How Light Refrcts Pge 439 Hndouts: Inquiry Investigtion 11-A Protrcr Grph Pper Pge 439 Complete Questions: #1-3 How Light Refrcts You cn picture bem of s

If strikes surfce of t n ngle, tht prt of bem tht enters first will slow down first. Notice in digrm tht this chnges direction of wves nd lso direction of ry of.

3 Pge 439 Activity: Investigting Refrction How Light Refrcts Pge 439 Hndouts: Inquiry Investigtion 11-A Protrcr Grph Pper Pge 439 Complete Questions: #1-3 How Light Refrcts You cn picture bem of s leding edge of wve, s shown in Figure At first, ll wves re prllel. n, wves re compressed s y enter nd slow down. If strikes surfce of t n ngle, tht prt of bem tht enters first will slow down first. Notice in digrm tht this chnges direction of wves nd lso direction of ry of. It is like line of skters chnging direction becuse skters t one end slow down on rough ice (Figure 11.34). strikes surfce of t n ngle, tht prt of How Light bem Refrcts tht enters first will slow down first this chnges direction of wves nd direction of ry of Figure Light cn be Figure Skter E slows down, mking entire row of skters turn. represented s series of wves tht compress nd chnge direction s y enter on n ngle. ngles of refrcted rys re usully mesured from, drwn rough t 9 surfce where ry crosses between two medi. When trvels from, with low refrctive index, Pge 439, with higher refrctive Pge 439 index, it bends wrd. D18 Inquiry Activity on pge 444 rough When trvels from denser (higher refrctive index) D18 Inquiry Activity less opticlly on pge 444 dense (lower Skter E slows down ngles refrctive index) of, refrcted it bends s hit rough ice. wy from. Figure Skter E slows down, mking entire row of skters turn. How Light Refrcts Figure Skter E slows down, mking entire row of skters turn. How rys ngle Light re mesured of incidence, Refrcts, nd ngle of refrction, θ Soldiers hiking in R, re glss You cn picture bem of s leding edge of wve, s from, drwn You cn picture bem of s leding edge of wve, s mesured from. Figure shown in Figure At first, ll wves ngles re prllel. of n, refrcted rys re usully mesured from mud. t shown shows in Figure ngle surfce At first, ll wves re prllel. n, of incidence, wves re compressed s y enter, drwn nd t 9 slow down. surfce If where ry crosses between wves re compressed s y enter nd slow down. If, nd ngle of refrction,, s () strikes surfce of two t n medi. ngle, When tht prt of trvels from, with low refrctive index, strikes surfce of t n ngle, tht prt of refrcts moving from () bem tht enters first will slow down, first. with Notice higher in digrm refrctive bem tht enters first will slow down first. Notice in digrm glss, nd from glss. tht this chnges direction of wves nd lso direction of tht this chnges direction of wves nd lso direction of index, it bends wrd. Figure Light moves () from glss nd from glss. ry of. It is like line of skters chnging direction becuse When trvels from denser ry of. It is like line of skters chnging direction becuse skters t one end slow down on rough ice (Figure 11.34). skters t one end slow down on rough ice (Figure 11.34). (higher refrctive index) Figure Light cn be Figure Light cn be less opticlly dense (lower represented s series of wves tht represented s series of wves tht refrctive index), it bends compress nd chnge θdirection i s compress nd chnge direction s y enter on n ngle. y enter on n ngle. wy from. Ry digrms model behviour of in mirrors nd lenses. 439 A B C D ngle E of incidence,, nd ngle of refrction,, re glss mesured from. Figure shows ngle of incidence,, nd ngle of rough refrction,, s () rough refrcts moving from () glss, nd from glss. Figure Skter E slows down, mking entire row of skters turn. ngles of refrcted rys re usully mesured from, drwn t 9 surfce where ry crosses between two medi. When trvels from, with low refrctive index,, with higher refrctive index, it bends wrd. When trvels from denser (higher refrctive index) less opticlly dense (lower refrctive index), it bends wy from. ngle of incidence,, nd ngle of refrction,, re glss mesured from. Figure shows ngle of incidence,, nd ngle of refrction,, s () refrcts moving from () (Picture A) glss, nd from glss. when trvels from ( low refrctive index), (with higher refrctive index) it bends wrd. (Picture A) Angle of Incidence θi will be lrger thn Angle of Refrction θr θi > θr D18 Inquiry Activity on pge 444 Figure Light moves () from glss nd from glss. Figure Light moves () from glss nd from glss. You cn picture bem of s leding edge of wve, s shown in Figure At first, ll wves re prllel. n, wves re compressed s y enter nd slow down. If strikes surfce of t n ngle, tht prt of glss bem tht enters first will slow down first. Notice in digrm tht this chnges direction of wves nd lso direction of ry of. It is like line of skters chnging direction becuse skters t one end slow down on rough ice (Figure 11.34). ngles of refrcted rys re usully mesured from, drwn t Ry digrms model behviour of in mirrors nd lenses surfce where ry crosses between two medi. When trvels from, with low refrctive index, when, with θtrvels R higher refrctive () from index, it slower bends wrd. When trvels from denser (higher fster refrctive index) less opticlly dense (lower Angle of refrctive index), it bends wy from. Refrction θr will be ngle of incidence,, nd lrger ngle thn of refrction, Angle, re glss mesured from. Figure θ of Incidence shows ngle of incidence, i θi, nd ngle of refrction,, s () (Picture refrcts B) moving from () glss, nd from glss. Figure Light moves () from glss nd from glss. rough Figure Skter E slows down, mking entire row of skters turn. θr > θi Figure Light cn be represented s series of wves tht compress nd chnge direction s y enter on n ngle. D18 Inquiry Activity on pge 444 D18 Inquiry Activity on pge 444 Figure Light moves () from glss nd from glss. (Picture B) Ry digrms model behviour of in mirrors nd lenses. 439 Ry digrms model behviour of in mirrors nd lenses. 439

Snell s Lw uses vlues for index of refrction clculte new ngle tht ry will tke s bem of strikes between two medi 1 n 1 n 2 2 n1 sinθ1 = n2 sinθ2 n = indices of refrction θ1 = ngle of incidence θ2

4 Snell s Lw uses vlues for index of refrction clculte new ngle tht ry will tke s bem of strikes between two medi 1 n 1 n 2 2 n1 sinθ1 = n2 sinθ2 n = indices of refrction θ1 = ngle of incidence θ2 = ngle of refrction 1 n 1 n 2 2 Homework Exmple: When psses from t n ngle of 6 from, wht is ngle of refrction? Red pg. 439 pg #1 from ech pge pg. 446 #1, 3-6 Prtil Refrction nd Reflection

5 Appliction: Rer View Mirror Write n explntion of this in your own words: Reding: Reflection nd Refrction in Rerview Mirror Wht is Prtil Reflection nd Refrction How does rer-view mirror work during dy? t night time? (For furr detils, see reding online)

Pge 440 Dispersion Dispersion refrction of white seprte wvelengths, or Dispersioncolours. A specil kind of refrction occurs in both dimond nd rindrops.

Since white contins mny colours, single bem of white A specil kind of refrction occurs in both dimond nd rindrops.

6 Pge 440 Dispersion Dispersion refrction of white seprte wvelengths, or Dispersioncolours. A specil kind of refrction occurs in both dimond nd rindrops. A dimond cn pper completely colourless nd yet glitter in ll colours Pge 443 of rinbow becuse mount of refrction is different for ech colour. Since white contins mny colours, single bem of white A specil kind of refrction occurs in both dimond nd rindrops. A cn enter dimond nd be split whole rinbow of colours, occurs in both imond cn pper completely colourless nd yet glitter in ll colours s shown in Figure This kind of refrction is clled dispersion. dimond nd f rinbow becuse mount of refrction is different for ech Dispersion is refrction of white seprte wvelengths, rindrops olour. Since white contins mny colours, single bem of white or colours. ght cn enter dimond nd be split whole rinbow of colours, common type of dispersion is in formtion of At most certin ngle, clled criticl ngle, refrcted ry of Figure This dimond is s shown in Figure This kind of refrction is clled dispersion. follows pth exctly long surfce of. Even though rinbow. When sun psses through rindrop, some is colourless but, due dispersion, it Dispersion is refrction of white seprte wvelengths, refrcts, it does leve twice,. once In wy, is trpped cts s prism split white up reflected. Some not is refrcted on entering rindrop its individul colours. r colours. inside on (Figure 11.40). nd once leving. Both refrctions cuse seprtion of white most common type of dispersion is in formtion of sun colours of rinbow (Figure 11.37). inbow. When sun psses through rindrop, some is 27 eflected. Some is refrcted twice, once on entering rindrop n! 1.00 nd once on leving. Both refrctions cuse seprtion of white n! un colours of rinbow (Figure 11.37). 4 s R i I c o t r sun 3 Totl Internl Reflection sun ht is split efrction in different s. b) T criticl ngle! 48.8 Figure () White sun is split colours of rinbow by refrction in source rindrop. An observer sees different colours from different rindrops. () Figure When ngle of incidence is grete thn criticl ngle, t droplet internl reflection occurs. () droplet Wht if ngle of sun incident ry is incresed even frr? ry is no longer refrcted. Insted, it is completely reflected bck inside. In n opticl fibre, is pssed end of fibre t n ngle greter thn criticl ngle. Becuse fibre is mde of glss, which hs higher index of refrction thn surrounding, ry is completely reflected inside fibre. rinbow rin drops sun Sug D20 rin drops Mirges Pge 443 rinbow Both tl internl reflection nd refrction ply role in forming mirge (Figure 11.41). A mirge is n imge of distnt object Lerning Checkpoint produced s refrcts through of different densities (Figure 11.42). Since rys pss through lyers of with 1. Wht is refrction? At certin ngle, clled criticl ngle, refrcted ry of Tkelower It Furr progressively indices of refrction, eventully is tlly Lerning Checkpoint follows pth exctly long surfce of. Even though 2. Define index of refrction. index hs mny uses, internllyrefrctive reflected. refrcts, it does not leve. In wy, is trpped including identifying gemsnes. 3. Wht Itrefrcts cn lso be used more, find spphire or dimond? 1. Wht is refrction? when stys within inside (Figure 11.40). concentrtion of solutions. Find ry out bout se nd or uses bend of 4. Wht direction does when it trvels from denser 2. Define index of refrction. Totl Internl Reflection Wht refrcts more, spphire or dimond? reflects completely from sky Wht direction bendwll whenof it trvels from denser offdoes inside denser less dense? (higher index of refrction) 5. How is refrction relted dispersion? rr thn pssing through wll less dense (lower index of refrction). Mirge 440 source refrctive index. Begin your t lessrydense reserch ScienceSource.? n! 1.00 n! 1.33 from cloud 5. How is refrction relted dispersion? more dense, cool cloud criticl ngle! 48.8 Criticl Angle UNIT D Light nd Geometric Optics observer Figur pudd ctu prod ner e less dense, hot Figure When ngle of incidence is greter thn criticl ngle, tl internl reflection occurs. hot pvement imge of cloud Suggested Figure Light Activity from n object in sky is refrcted due difference in density of Wht if ngle of incident ry is incresed even frr? D20 Design Lb on pge 446 ry is no longer refrcted. Insted, it is completely reflected bck bove pvement compred with higher up. inside. In n opticl fibre, is pssed end of fibre t n ngle greter thn criticl ngle. Becuse fibre is mde of glss, which hs higher index of refrction thn surrounding, ry is completely reflected inside fibre. Mirges Ry digrms model behviour of ligh

7 Homework Red pg pg. 447 #10, 11, 12, 17, 18

Light and Optics Propagation of light Electromagnetic waves (light) in vacuum and matter Reflection and refraction of light Huygens principle

$Light and Optics Propagation of light Electromagnetic waves (light) in vacuum and matter Reflection and refraction of light Huygens principle$ Light nd Optics Propgtion of light Electromgnetic wves (light) in vcuum nd mtter Reflection nd refrction of light Huygens principle Polristion of light Geometric optics Plne nd curved mirrors Thin lenses