Does Huygens’ principle apply to sound waves? To wateb2sngl:76kw(n ot0av r waves? Explain.

What is the evidence that e*t3 ka/bxm2e light is energy?

Why is light sometimes described as rays and sometimeskbt0px) 6jd 5z;)d ,ilu 3scgz as waves?

We can hear sounds around corners, but we cannot see around corners;5-kqhtza62)x8* n9 kx 9r 3jsoqkyg bq yet both sound and light are waves. Explain the differencq nz5t -*k)gx2 h3aysq9bqjxk9 rok86e.

If Young’s double-slit experm;tguld j63f 7l35g mmiment were submerged in water, how would the fringe pattern be chandmm6 uflmg7 t5;l3 3gjged?

Monochromatic red light is incident eysm3l8scj.um*sy n )5 nb+ m)on a double slit, and the interference pattern is viewed on a screen some distance away. ymlmsy )85 cebms3s) jn.*n+u Explain how the fringe pattern would change if the red light source is replaced by a blue light source.

Two rays of light from the same source destructively:;1c 1c )vfsn hrgut2r; vfc;v interfere if their path lengths difvvnthcr21ur)fc:g;v ;;1s cf fer by how much?

Why was the observation of the double-slit interference pattern more c2 c-.cwcro co7onvincing evidence fcr 7occwoc -.2or the wave theory of light than the observation of diffraction?

Compare a double-slit experiment for sound waves to that for light wavesuqij.7 q9ff3 r. Discuss the simij qfrqf3u7i9.larities and differences.

Why doesn’t the light from the two headlights of a distant car proxx df- i/5 rdd+nw*b*nduce an interference pa +n-**d f/wdixnrdbx5ttern?

Suppose white light falls on the two slits of Fig. 24–7, butrk p xra6nlb*(b g*)m5 one slit is covered by a red filter (700 nm) and the other by a blue filter (450 nmbp *)rg*r5a6k(lxb m n). Describe the pattern on the screen.

When white light passes through a flat l.gifo ii6r(* piece of window glass, it is not broken down into colors as iti*go(ilr6f i. is by a prism. Explain.

For both converging and diverging lenses, discuss how the focal lewc os0;7 o s.d8jruaj*ngth for red light diffe oa8s0j*duo7j;sw c r.rs from that for violet light.

A ray of light is refracted tht7/v /iko (1oftxnif5m7 py 5srough three different materials (Fig. 24–55). Rank the materials acc (p5/ifn1 vmi7 7koox/ttf5syording to their index of refraction, least to greatest.

Hold one hand close to your eye and focus on a distant li9qv -.ct yu d1*w)evz7ak bsy6ght source through a narrow slit between two fingers. (Adjust your fingers to obtain the best pattern.) Describe the pattern that yu- c ydwy*9bvk.t6v1)seqaz7 ou see.

What happens to the diffractionifn t5f;- gas/vx)rw6 pattern of a single slit if the whole apparatus is immersed in (a) water, (b) a vacrtvi /5fxa6 w;-fgs)nuum, instead of in air.

For diffraction by a single slit, xmw* edi)e sp02 qm:z/zx5p8 nwhat is the effect of increasing (a) the slit width, and (b) the waveleng5mzex * )pmz8: q2wsi/0exn pdth?

What is the difference in the interference patterns fld75b,fyi8r tvn +l+t7 koak- ormed (a) by two slits $^{-4}\;cm^2$ apart, (b) by a diffraction grating containing $10^4lines/cm$?

For a diffraction gratingm-ofz p kjy2mj;t5;-m , what is the advantage of (a) many slits, (b) closely spaced slittp o2 kzmf;mjy5m-- ;js?

White light strikes (a) a diffraction grating, and (b) a prism.o)n jdhzuaa 8; u(z+3;lajz:f A rainbow appears on a wall just below the direction of the horizontal incident beam in each case. What is the color of the top of the3;aza(zzo8 fl : jh ;u+du)anj rainbow in each case? Explain.

For light consisting of wavelengths betwehpqodgva; ,0*qv0ot4en 400 nm and 700 nm, incident normally on a diffraction grating, for what orders (if any) would there be 0t,qa;hodoq4 vvpg *0overlap in the observed spectrum? Does your answer depend on the slit spacing?

Why are interference fringes noticeable only for a thin film like a soap bubble t*ywj 3s8 2vlcand not fo2w l* j3yvtc8sr a thick piece of glass, say?

When a compact disk (CD) is held at an angle in white light, the reflech g9ka9(+dcak( ehzs( ted light is a full spectrum (Fig. 24–56). Explain. +hgsh d(k9((k az ce9aWhat would you expect to see if monochromatic light was used?

Why are Newton’s rings (Fig. 24–31) closer together farther from the gm/b5m h(j2 tmj3n1owqtc2w4 center?

Some coated lenses appear greenish yellow when seen by reflected light. What :-jw7nwo+m :s zjw,ftwavelengths do you suppose the coating is f:,w:+-jwnw7omtj zs designed to transmit completely?

A drop of oil on a pond appears bright at its edgnf 2+0csab.u. enrly9 es, where its thickness is much less than the wavelengths of visible light. What can you say about tnlfc na0s9rb.y+.2 euhe index of refraction of the oil?

What does polarization tell us aboutj, ,k :cs)tv:r;o 6g 5qbkvdho the nature of light?

Explain the advantage of polarized sunglaj:60ecl fer,rsses over normal tinted sunglasses.

How can you tell if a p+uo58 racrzcnvgq4d2/c7 e 2s kfdi10air of sunglasses is polarizing or not?

Two polarized sheets rotated at an k;zra6 gh7 4- ihxvce:angle of 90$^{\circ}\,$ with respect to each other will not let any light through. Three polarized sheets, each rotated at an angle of 45$^{\circ}\,$ with respect to each other, will let some light through. What will happen to unpolarized light if you align four polarized sheets, each rotated at an angle of 30$^{\circ}\,$ with respect to the one in front of it?

What would be the color of the sky if the Earth had nolp*a6kn9 go4thw 4dd 1 atmosphere?

If the Earth’s atmosphere were 50 times denser than it is, w lkg(ue g6w7b-ould sunlight still be white, or would it be some othegw(-u6 kelbg7r color?

  Monochromatic light falling on two slits 0.016 mm al xbmj0* 3(p72zbw rbfpart produces the fifth-order fringe b7rf*z b(m3b0wp ljx2 at an 8.8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 610 nm light is observed at an an,bz+lc- m;rw,bor*jf oc ;anh;u3me) gle of 18$^{\circ}\,$ when the light falls on two narrow slits. How far apart are the slits?    $\mu m$

  Monochromatic light falls on two very narrow slits . 6 g,2g wt m7odry44waq-htwl0.048 mm apart. Successive fringes on a screen 5.00 m away are 6.5 cm apart near the center ofgla4dg o-,2qwy .mtwt4 r 67wh the pattern. Determine the wavelength and frequency of the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of light from a He-Ne laser, with a wavelength 656 nm, falls *st5v05h) tsguq*eu aon two very narrow slits 0.060 mm apart q u5t *se5th0)gasvu*. How far apart are the fringes in the center of the pattern on a screen 3.6 m away?    cm

  Light of wavelength 680 nm falls on two slits a;y:t+ fji6 ozbko gkmz*-*cp;nd produces an interference pattern in which the fourth-order fringe is 38 mm from the central fringe on a screen 2.0 m amgo;-6 *o*+pi bjtk; y zk:zfcway. What is the separation of the two slits?    mm

  If 720-nm and 660-nm light passes through two slits 0.58 mm apart, how far apart5 8* o9hp bpi,govsr5s are the second-order fringes for these two wavelengths on a screenrp5g *sbp9h,i5vsoo 8 1.0 m away?    mm

  In a double-slit experiment, it is fnh )78lfsv e1aound that blue light of wavelength 460 nm gives a second-order maximum at a certain location on the screen. What wavelength of visible light would have a minimum at the same loal fe sv781h)ncation?    nm

Water waves having parallel crests 2.5 cm apart pass through two openings 5.0 cmfc*.f t xpas*: apart in a bos*ca :. fftp*xard. At a point 2.0 m beyond the board, at what angle relative to the “straight-through” direction would there be little or no wave action?

Suppose a thin piece of glasht vfb3q0whur,s0 f s6yx)y1+s is placed in front of the lower slit in Fig. 24–7 so that the two waves enter the slits 18hx0vu1w3 )6q,0fb ys+r hst yf0$^{\circ}\,$ out of phase (Fig. 24–57). Describe in detail the interference pattern on the screen.
24-7
24-57

  In a double-slit experk)wdp+(bb,lu hjs 33 re8bv9diment, the third-order maximum for light of wavelength 500 nm is located 12 mm from the central bright spot on a screen 1.6 m from the slits. Light of wavelength 650 nm is then projected through the same slits. How far frovkdeubbjb3 8l+9s pw (h)d3,r m the central bright spot will the second-order maximum of this light be located?    mm

  Two narrow slits separated by 1.0 mm are illuminated by 544 nm ypk mb e3a0e l)f/9vyv2a0a4 56mnxgklight. Find the distance between adjacent bright fringes on a scrk9g0e m6) b0y aanpk f/3y2axvvle5m 4een 5.0 m from the slits.    mm

  Light of wavelength 480 nm in air falls on two sli u0jewe /uzj5ehsb2;8ts $6.00 \times10^{-2 }\;mm$ apart. The slits are immersed in water, as is a viewing screen 40.0 cm away. How far apart are the fringes on the screen?    mm

  A very thin sheet of plastic (n=1r zk7d19xryrjc 5e 5m,.60) covers one slit of a double-slit apparatus illuminated by 640-nm light. The center point on the screen, instead of being a maximum, is dark. What is the (minimum) thickness or,cxzy e759 rd1jm5r kf the plastic?    nm

  By what percent, approximately, does the speed ok( u7 31x dj,xwz,ozqyf red light (700 nm) exceed that of violet light (400 nm) in silicate flint glass? (See Fig. 24–zyw(1 , kqz3o7 ujdx,x14.)    %

  A light beam strikes a piece ;/vufs. y txl8of glass at a 60.00$^{\circ}\,$ incident angle. The beam contains two wavelengths, 450.0 nm and 700.0 nm, for which the index of refraction of the glass is 1.4820 and 1.4742, respectively. What is the angle between the two refracted beams?    $^{\circ}\,$

  A parallel beam of light containing two wavelenh(z*21wzvhh5by h1 4zm(g z o/no+ -yvcwxo i+gths, $\lambda_1\;=\;450\;nm$ and $\lambda_2\;=\;650\;nm$, enters the silicate flint glass of an equilateral prism as shown in Fig. 24–58. At what angle does each beam leave the prism (give angle with normal to the face)?
$\theta_{d1}$    $^{\circ}\,$ from the normal
$\theta_{d2}$    $^{\circ}\,$ from the normal

  If 580-nm light falls on a slit 0.0440 mm wid 23,w9x7s9vg xj obrqp9arq z2e, what is the full angular width of the central diffracs2qxrb7ao9v2 3 wq9z9xpg ,j rtion peak?    $^{\circ}\,$

  Monochromatic light fu,wrnn o4p-vm5b ee80alls on a slit that is $ 2.60\times10^{ -3}\;mm$ wide. If the angle between the first dark fringes on either side of the central maximum is 35.0$^{\circ}\,$ (dark fringe to dark fringe), what is the wavelength of the light used?    nm

  Light of wavelength 520 nm falls onh qkwz8scow; w7nf,1( a slit that is $ 3.20\times10^{ -3}\;mm$ wide. Estimate how far the first brightish diffraction fringe is from the strong central maximum if the screen is 10.0 m away.    m

  A single slit 1.0 mm wide is illuminated by 450-nm js 6+pjv: zrp;ca3hz0light. What is the width of the centrc;zrz vps6:jjpha0 3+ al maximum (in cm) in the diffraction pattern on a screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm falls oniwl;;vr(zh y8)u9 osl a slit. If the angle between the first bright fringes on either sio livl(9yz;ur h8 ;s)wde of the central maximum is 32$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central diffraction peak on a screen 2.30 m behind a 0.0348ix3;zfw5u +0akc.kxc-mm-wi 0+ck.wik;5c3z fuxaxde slit illuminated by 589-nm light?    cm

  When blue light of wavelength 440 nm falls on a si0e4 m 6 ceywjvz d;emko4,t5m:ngle slit, the first dark bands on eithee4em5:kv4em; 6ot0wj mz,cydr side of center are separated by 55.0$^{\circ}\,$. Determine the width of the slit.    $ \times10^{-7 }\;m$

  When violet light of wavelength 415 nm falls on a single slit, it creates a ce-ks79 6l6 k+o meyyfyentral diffraction peak that6lm+ee 9 7ys k-6yoyfk is 9.20 cm wide on a screen that is 2.55 m away. How wide is the slit?    mm

  If a slit diffracts 650-nm light so that the kq7q1fc*hjczkyks6 hh qb/,rs26 0g/ diffraction maximum is 4.0 cm wide on a screen 1.50 m away, what will be the width of the diffraction maximum for light of wavel r qgkch/,/hkj17sbckfsq qy6*z06 2hength 420 nm?    cm

For a given wavelengtdogyt7nsd+kd vw j+ee( j cqv,t+83 15h $\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm7) z g91zcdprt light produce a second-order maximum when falling on a grating whost) dzp9 zr71gce slits are $1.45 \times10^{-3 }\;cm$ apart?    $^{\circ}\,$

  A $3500-line/cm$ grating produces a third-order fringe at a 28.0$^{\circ}\,$ angle. What wavelength of light is being used?    nm

  How many lines per centimeter does a grating have if the third-order o/7m8xcct1 j,,o pjfvpp, nj e2ccurs at an 18. x,pcjpnfp/,et7m 182,ojjvc 0$^{\circ}\,$ angle for 630-nm light?    $ \times10^{3 }\,lines/cm$

  A grating has $8300\;lines/cm$. How many complete spectral orders can be seen (400 nm to 700 nm) when it is illuminated by white light?   

  The first-order line of 589-nm light falling on a diffraction grating is obserri;1 j:3oths gved ag j :tir13os;ht a 15.5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction grating has5. /nz ngwcun0 $ 6.0\times10^{ 5}\;lines/m$. Find the angular spread in the second-order spectrum between red light of wavelength $ 7.0\times10^{-7 }\;m$ and blue light of wavelength $ 4.5\times10^{-7 }\;m$.    $^{\circ}\,$

  Light falling normall1gak q cd z-*fz8v-no,y on a $9700-line/cm$ grating is revealed to contain three lines in the first-order spectrum at angles of 31.2$^{\circ}\,$, 36.4$^{\circ}\,$, and 47.5$^{\circ}\,$. What wavelengths are these?
$\lambda_{31.2}$    nm
$\lambda_{36.4}$    nm
$\lambda_{47.5}$    nm

  What is the highest spectral or oa5 *y;nt*jirq fxl-*der that can be seen if a grating with 6000 lines per cm aql;f t5* xn yj*-*oiris illuminated with 633-nm laser light? Assume normal incidence.   

  Two (and only two) full spectral orders can be seen on either side of the cenf u podlfe16gv2q:7-d tral maximumpdvq-o 72:lf 1 f6edgu when white light is sent through a diffraction grating. What is the maximum number of lines per cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containing wavelengths from 410 nm to 750 pa 8d:) bg7nbxnm falls on a grating with)gp: a7bd8nbx $8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which produces monochromatic li/.dj/:ub4n(zrtb,j afn) 5 ikmib9wy ght of a known wavelength $\lambda\;=\;6.328\times10^{-7 }\;m$ is used to calibrate a reflection grating in a spectroscope. The first-order diffraction line is found at an angle of 21.5$^{\circ}\,$ to the incident beam. How many lines per meter are there on the grating?    $ \times10^{ 5}\;lines/m$

  Two first-order spectrum lv qxucl*04 mq9 nga8q4ines are measured by a $9500-line/cm$ spectroscope at angles, on each side of center, of +26$^{\circ}\,$ 38$^\prime$,+41$^{\circ}\,$ 08$^\prime$ and -26$^{\circ}\,$48$^\prime$,-41$^{\circ}\,$ 19$^\prime$. What are the wavelengths?
$\lambda_{26.72^{\circ}}\;=\;$    nm
$\lambda_{41.23^{\circ}}\;=\;$    nm

  If a soap bubble is 120 nm thick, what wavelength is most strongly reflected at r* p z q08egzno(v)*yhthe center of the outer surface when n0zy(ovpze*r 8* qhg)illuminated normally by white light? Assume that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the dark fringes in Example 24–8 ifskz- u+2f voezs 9j::ab rz, drt+2mz(v nf3l4 the glass plates are each 26.5 cm longumzb-: z +t:szv, 2n adfe s (4lr+ov29krzf3j?    cm

  What is the smallest thickness of -9.fx16+rvr c 51l guszhct goa soap film $(n\;=\;1.42)$ that would appear black if illuminated with 480-nm light? Assume there is air on both sides of the soap film. $t_min$    nm

  A lens appears greenish yel4 rla;wh 6aygogd-35slow ($\lambda\;=\;570\;mm$ is strongest) when white light reflects from it. What minimum thickness of coating $(n=1.25)$ do you think is used on such a glass $(n=1.52)$ lens, and why? $t_{min}$    nm

  A total of 31 bright and 31 dark Newton’s rings (notyl0(td n lj,.c inoxh)m:f6j : counting the dark spot at the center) are observed when 5jit ldl:m6:0fcnnj( . ,oyx)h50-nm light falls normally on a planoconvex lens resting on a flat glass surface (Fig. 24–31). How much thicker is the center than the edges?    $\mu m$

  A fine metal foil separates one h 3x,kqx;f,0z0qb cdwscc -+e end of two pieces of optically flat glass, as in Fig. 24–33. When light of q3xh0-;0f, xbkqcec,c w+zd swavelength 670 nm is incident normally, 28 dark lines are observed (with one at each end). How thick is the foil?    $\mu m$

  How thick (minimum) should the air layer be between two mf6y.3h st gp2++p07phfd b7 sbjpl 2sflat glass surfaces if the glass is to appear bright when 450-nm lightps 2s m 7pf+gpsl hy2+3df.b0h7tj6bp is incident normally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, suy f70u2.eqnxyu *z6yf spected of being a stolen diamond $(n=2.42)$ is submerged in oil of refractive index 1.43 and illuminated by unpolarized light. It is found that the reflected light is completely polarized at an angle of 59$^{\circ}\,$. Is it diamond? ----待选择----yesno 

  A thin film of alcoho 6bge.w lj xuk 1hwvr0wn4/7+fl $(n=1.36)$ lies on a flat glass plate $(n=1.51)$. When monochromatic light, whose wavelength can be changed, is incident normally, the reflected light is a minimum for $\lambda\;=\;512\;nm$ and a maximum for $\lambda\;=\;640\;nm$ What is the minimum thickness of the film?    nm

  When a Newton’s ring apparatus (Fig. 24–31) is immers9rf3 ihnm28uf3vz fu8ed in a liquid, the diameter of the eighth dark ring decreases from 2.92 cm to 2.48 cm. What is the refractive index of the liq3h3f 8zi 98fuvfnu2rm uid?   

  What is the wavelength of the light entering an interferov8 ;j.ewijw cz(d9zjl 3; 0;dloqgmd6meter if 644 bright fringes are counted when the movable mirror moves 0.22 v8qz;3(lo ;cdz id l9djm.6ge;w0jwj5 mm?    nm

  A micrometer is connected to the movable mirror of an interfero+9ry *3vp hd(eb d4*vfyol8cmmeter. When the micrometer is td3p8 *cldb 94 vvr(myh+e*yofightened down on a thin metal foil, the net number of bright fringes that move, compared to the empty micrometer, is 272. What is the thickness of the foil? The wavelength of light used is 589 nm.    $\mu m$

  How far must the mirrovg ju-7 a 1sz5amz8q4br $M_1$ in a Michelson interferometer be moved if 850 fringes of 589-nm light are to pass by a reference line?    mm

  One of the beams of an interferometer 8yvnj sljn.yh mmvx 92,kf*+7(Fig. 24–59) passes through a small glass container containing a cavity 1.30 cm deep. When a gas is allowed to slowly fill the container, a total of 236 dark fringes are counted to move past a reference line. The light used has a wavelength of 610 nm. Calculate the index of refraction of the g mxvj2syhv97+n m*,8. yj lfnkas, assuming that the interferometer is in vacuum. $n_{gas}$

  

  Two polarizers are oriented at sluz9b9qf;f o lo)6 y:65$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s angle for an air–glass60ho:syadl8aff g pbo- - 23mq $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submergeddb9f pd/ *ad c(yq(qr8 in water if the light is hitting the/qy9ddprfa 8b*(q( dc diamond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the light passing through them is a ma( 3zf4qir fhd(vq;xv:t4z-j y ximum. At what angle shouqrh3(xfzd ; z:-jviy 44tq(vfld one of them be placed so that the intensity is subsequently reduced by half?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as t0as+o .l q(dvl.kb2 ;fxr;fnzo reduce the intensity of the incident ufkafrd+v bs.l;(.02l noxq;z npolarized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are orient*bz); k :3holk lti v9b1s3ozsed at 40$^{\circ}\,$ to each other and plane-polarized light is incident on them. If only 15% of the light gets through both of them, what was the initial polarization direction of the incident light?    $^{\circ}\,$

  Two polarizers are oriented a7g.s au w4u+srt 38.0$^{\circ}\,$ to one another. Light polarized at a 19.0$^{\circ}\,$ angle to each polarizer passes through both. What percent reduction in intensity takes place?    %

  What would Brewster’s angle be for ref * *onlrzt(;gklections off the surface of water for light coming from beneath the surf( *;*rzn lgkotace? Compare to the angle for total internal reflection, and to Brewster’s angle from above the surface.
If the light is coming from water to air, $\theta_{p}$    $^{\circ}\,$For the refraction at the critical angle from water to air $\theta_c$   $^{\circ}$ If the light is coming from air to water $\theta_p'$   $^{\circ}$

  Unpolarized light passes through five successive Pnrw5: :sa7hkx olaroid sheets, each of whose axis makes a 47sr5 nk: xhaw:5$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength ue17av,o0bcn b gp46qz pl6*y$ 5.0\times10^{7 }\;m$ passes through two parallel slits and falls on a screen 4.0 m away. Adjacent bright bands of the interference pattern are 2.0 cm apart.
(a) Find the distance between the slits.    mm
(b) The same two slits are next illuminated by light of a different wavelength, and the fifth-order minimum for this light occurs at the same point on the screen as the fourth-order minimum for the previous light. What is the wavelength of the second source of light? $\lambda_2$    $ \times10^{-7 }\;m$

  Television and radio wav c2zv l83)1 dtxcq+egv1k/)cil i*brb es reflecting from mountains or airplanes can interfere liqe 21cbi*tgz1x d8rl3cb+/cv) )vkwith the direct signal from the station.
(a) What kind of interference will occur when 75-MHz television signals arrive at a receiver directly from a distant station, and are reflected from a nearby airplane 118 m directly above the receiver? Assume $\frac{1}{2}\;\lambda$ change in phase of the signal upon reflection.  ----待选择----constructivedestructive 
(b) What kind of interference will occur if the plane is 22 m closer to the receiver?  ----待选择----constructivedestructive 

  Red light from three separate sournbdf+e iw6 hyczq62*;ces passes through a diffraction grating with fcz bqd*;yh6 2i+ w6en$ 3.00\times10^{5 }\;lines/m.$ The wavelengths of the three lines are $ 6.56\times10^{-7 }\;m$ (hydrogen), $ 6.50\times10^{ -7}\;m$ (neon), and $6.97 \times10^{ -7}\;m$ (argon). Calculate the angles for the first-order diffraction lines of each of these sources. $\theta_{h}$    $^{\circ}\,$ $\theta_{n}$    $^{\circ}\,$ $\theta_{a}$    $^{\circ}\,$

  Light of wavelength 590 nm passes tpcix(uo/dld.k (t 5/ ghrough two narrow slits 0.60 mm apart. The screen is 1.70 m away. A second source of unknown wavelength produces its second-order fringe 1.33 mm closer to the central maximum than the 590-nm light. Wha lgi .(udo/tkdx( p/5ct is the wavelength of the unknown light? $\lambda_2$    nm

A radio station operating db 422jnwz 3.v jvuat-at 102.1 MHz broadcasts from two identical antennae at the same elevation but separated by an 8.0-m horizontal distance d, Fig. 24–60. A maximum signal is found along the midline, perpendicular to d at its midpoint and extending horizontally in both direction 3zbnjw2v4t vda2u-.js. If the midline is taken as 0$^{\circ}\,$, at what other angle(s) $\theta$ is a maximum signal detected? A minimum signal? Assume all measurements are made much farther than 8.0 m from the antenna towers.

  A teacher stands well ba*f6k/zyk 6iq4.vmet u ck from an outside doorway 0.88 m wide, and blows a whistle of frequency 750 Hz. Ignoring reflections, estimate at what angle(s) it is not possible to hear the whistle qmk6y6 *ik/t fu4e.vzclearly on the playground outside the doorway.    $^{\circ}\,$ either side of the normal.

If parallel light falls on a single spf 1i*v v9(pv rt*z )f8lw(rcalit of width D at a 30$^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain2ge, kfu udc 7zlhum sgan 90:ktg-ws ;515gp) beetle have a series of parallel lines across them. When normally incident 460-nm light is reflected from the wing, the wing appears bright when viewed at an antm5k 2d-g;pwg:c ks 0u7u9aul)gz1nghf, se5 gle of 51$^{\circ}\,$. How far apart are the lines?    nm

  How many lines per cedptq1zi.nq( 9vg u5 j,ntimeter must a grating have if there is to be no second-order spectrum for any visible 59,pnq j(v.igdztq1u wavelength?   $ lines/cm$

Show that the second- and third-order spectra of white lxytan 9(00 iiqight produced by a diffraction grating always overlap0(i0a yn9i qxt. What wavelengths overlap exactly?

  When yellow sodium lig1f)/:d9q 1prhdcrbsnht, $\lambda\;=\;$ falls on a diffraction grating, its first-order peak on a screen 60.0 cm away falls 3.32 cm from the central peak. Another source produces a line 3.71 cm from the central peak. What is the wavelength of the new source? How many $lines/cm$ are on the grating?
   nm
  $ lines/cm$

  Light is incident on a diffraction gratin :7p.+deo 5uzkcylcl7g with and the pattern is viewed on a screen 2.5 m from the grating. The incident light beam consists of two wavelengths, p7y: du occ7klz.5+el$\lambda_1\;=\; 4.6\times10^{ -7}\;m$ and $\lambda_2\;=\; 6.5\times10^{ -7}\;m$. Calculate the linear distance between the first-order bright fringes of these two wavelengths on the screen.    m

What is the index of refraction of a clear material if a minimum of 150*rssd *co )f;87:b hr6jikjjr nm thickness of it, when laid on glass, is needed to reduce reflection to nearly zero when light rbih;* 8dfo:j7jrrk )s*6j c sof 600 nm is incident normally upon it? Do you have a choice for an answer?

  Monochromatic light of va cw)((vl mo2h-g1n4m8 6g rw 9 ;pl(eamwjzxduriable wavelength is incident normally on a thin sheet of plastic fil g v )r1px2lm(w6ueh(dz9amj4c8gw-w o (m; lnm in air. The reflected light is a minimum only for $\lambda\;=\;512nm$ and $\lambda\;=\;640nm$ in the visible spectrum. What is the thickness of the film $(n=1.58)$? [Hint: Assume successive values of m.]    nm

  Compare the minimum thickness needed for 0o lo-de0p .pvan anti-reflective coating $(n=1.38)$ applied to a glass lens in order to eliminate
(a) blue (450 nm),    nm
(b) red (700 nm) reflections for light at normal incidence.    nm

  What is the minimum (non-zero) thickness for the .+a:f aqs7ymx av9)87ybb j woair layer between two flat glass surfaces if the glass is to appear dark when 640-nm light is incident 7javbs ma 9f)oy+7w: q. axb8ynormally?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the light transmittedy/ je *f k kdk1-mh3k5spkb(0s through a thin film layered on a flat piece of glass. Draw a diagram, similar to Fig. 24–30 or 24–36, and describe the conditions required fbk3kkk5sjkhm/f(*s 0- 1 pedyor maxima and minima. Consider all possible values of index of refraction. Discuss the relative size of the minima compared to the maxima and to zero.
24-30
24-36

  At what angle above the horizon is the Sun when baf(o0wqyz-y l+:gdda 2wv.)light reflecting off a smooth lake is polarized most str q+ dwob)d wv-.azly(a:fgy20ongly?    $^{\circ}\,$

  At what angle should the axes of tw4kwp0rlsge k-0/0q 3tho k) kdo Polaroids be placed so as to reduce the intensity of the incident unpolarized light by an additional factor (after the first Polarp 0 kwkg dsoe)k4-t0khlq/03r oid cuts it in half) of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light falls on two pol:3oenj u btnx(t-1i:harizer sheets whose transmission axes are at right angles. A third polarizer is placed between the first two so that its axis makeijtob :(1xn hunt3:e- s a 62$^{\circ}\,$ angle with the axis of the first polarizer.
(a) What fraction of the incident light intensity is transmitted?    $I_0$
(b) What if the third polarizer is in front of the other two?

Four polarizers are placed in succession with their :etop55 mn0t4dagd q: unh55mfd brl/ ,0d;umaxes vertical, at 30$^{\circ}\,$ to the vertical, at 60$^{\circ}\,$ to the vertical, and at 90° to the vertical.
(a) Calculate what fraction of the incident unpolarized light is transmitted by the four polarizers.
(b) Can the transmitted light be decreased by removing one of the polarizers? If so, which one?
(c) Can the transmitted light intensity be extinguished by removing polarizers? If so, which one(s)?

  A laser beam passes throug51bf c;2 rbkbph a slit of width 1.0 cm and is pointed at the Moon, which is approximately 380,000 km from the Earth. Assume the laser emits waves of wavelength 630 nm (the red light of a He-Ne laser). Estimate the width of the beam when it re b 2bck1rp5b;faches the Moon.    km

  A series of polarizers qju-awtpj f7zm- u:jv*m8v. g4 q:l-jare each placed at a 10$^{\circ}\,$ interval from the previous polarizer. Unpolarized light is incident on this series of polarizers. How many polarizers does the light have to go through before it is $\frac{1}{4}$ of its original intensity?   

  A thin film of soap gk44 *purpjuon eq ;):$(n=1.34)$ coats a piece of flat glass $(n=1.52)$ .How thick is the film if it reflects 643-nm red light most strongly when illuminated normally by white light?    nm

  Consider two antennas r)/e4n+yf s3 vbt+ - qgflwmsf*adiating 6.0-MHz radio waves in phase with each other. They are located at poings e wlm f)s3+ yntfqf*-vb+4/ts $S_1$ and $S_2$, separated by a distance $d\;=\;175m$, Fig. 24–61. What are the first three points on the y axis where there will be destructive interference? (Destructive interference in this case means that a radio receiver placed at that point would pick up no signal).    m    m    m

  A parallel beam of light containing two wavelengths, 420 nm and 650b kv2q5n3vd;hphkb6v r jkd2-b9)(3z1jtplj nm, enters a silicate flint glass equilateral prism (Fig. 1 t)pkj63b3h bb 5hk(pdj9-lrk;2j zv2vdqn v 24–58).
(a) What is the angle between the two beams leaving the prism?    $^{\circ}\,$
(b) Repeat part (a) for a diffraction grating with    $^{\circ}\,$

  A Lucite planoconvex lens has one flat surface a xlc(w 01rvlc)nd one with $R\;=\;18.4\,cm$ It is used to view an object, located 66.0 cm away from the lens, which is a mixture of red and yellow. The index of refraction of the Lucite is 1.5106 for red light and 1.5226 for yellow light. What are the locations of the red and yellow images formed by the lens? [Hint: See Section 23–10.]
$d_{i-red}$    cm
$d_{i-yellow}$    cm