Does Huygens’ principle apply to sounmnscho+w0 5vzge1c2- d waves? To water waves? Explain.

What is the evidence thatjg w-iw 3zf2vw .x;vo;xqy8+m light is energy?

Why is light sometimts7riqt+ltk ;y)fws p9 xgjs43 3n7 .pes described as rays and sometimes as waves?

We can hear sounds around corners, but we cannot see ar, gdc x) o(f+tpaj3jwf6j6o d5ound corners; yet both sound and aogdpj65(jf+d6 )tj cf3o x, wlight are waves. Explain the difference.

If Young’s double-slit experiment xm)ysx +aqr6x.b bj91were submerged in water, how would the fringe pattern x. 9q maj6)+bxsbyr1 xbe changed?

Monochromatic red light is incident on a double slit, and the interferej4 q7+0 rcqprgnce pattern is viewed on a screen some distance away. Explain how the fringe pattern qgr0j4rq 7cp+would change if the red light source is replaced by a blue light source.

Two rays of light from the same source desoy6 pisqu d*6m/ jn)i/o*9hsa tructively interfere if their path lengths differ by hoau6nyi*ssi)d/o/9 6 qjp ohm*w much?

Why was the observation of the double-slit interference pattery7d1 bhi7zv:qu2ml qnap- m5 u5bl03pn more convincing evidence for the wave d37pqz 27lh:-p m05y5nb qa ulv bui1mtheory of light than the observation of diffraction?

Compare a double-slit c q16sc7rlo,ghunbzy inn 2**qf .0f8 experiment for sound waves to that for light waves. Discuss the similaritiez 0*, u*8gq bf cfycl1nisn2n6hr7q .os and differences.

Why doesn’t the light from the two headlights of a distkqp(t 7*jbiu1 ant car produce an interferencep( uk7ijb *q1t pattern?

Suppose white light falls on the two slits of Fig. 24–7, but ows v8*x9jxih :ne slit is covered by a red filter (700 nm) and the other by a blue filter (450 nm). Describe the pattern on the scree*vhxs9 :wj 8ixn.

When white light passjus9ff 9cv vfk*y/lb2)tuoty7/ -4rres through a flat piece of window glass, it is not broken down into cors rf/vvkl u7u249jo */b -y)ft9tycflors as it is by a prism. Explain.

For both converging and diverging lenses, discfc0m0s9x6z 2zud 1okquss how the focal length for red light differu6smz90xk1czo 2 dfq0s from that for violet light.

A ray of light is refracted through three different materialsca 9qt)1j* exv;uuo1qg74 b ky (Fig. 24–55). Rank the mate;1uqevb974 t)*jy1xqca kuogrials according to their index of refraction, least to greatest.

Hold one hand close to your eye and focus on a dia tnfn+m.sof2: ,l g)bstant light source through a narrow slit b.2tm o+nl)afb:,fgns etween two fingers. (Adjust your fingers to obtain the best pattern.) Describe the pattern that you see.

What happens to the diffraction pattern of a single slit if twjh.a pt:p t(:he whole apparatus is immersed ina jtwtp :p:.h( (a) water, (b) a vacuum, instead of in air.

For diffraction by a single slit, what is the effect of- / h j;da l-ut53gvvxwgzpx0bpg1.2m increasing (a) the slit width, and (b)t ;-d xwp 2350p ulxm-.hzagvvj/g1gb the wavelength?

What is the difference in the interference patterns fpls1+5r2j-*h6y 7cz gre sv cwormed (a) by two slits $^{-4}\;cm^2$ apart, (b) by a diffraction grating containing $10^4lines/cm$?

For a diffraction grating, wht) ,li.q)(x lg: 3+id-dfxlcc c6yisqat is the advantage of (a) many slits, (b) closely space6)cf+gt:ldl ,iic )x qiyl-3sq (x d.cd slits?

White light strikes (a) a diffraction grating, and (b) a prismm5/emzndd+ ) k. A rainbow appears on a wall just below the direction of the horizontal incident beam in each case. What is the znddm)/m ek5 +color of the top of the rainbow in each case? Explain.

For light consisting of wavelengths between 400 nm and 700 nm,bk+aj+v;a nb 7 incident normally on a diffraction grating, for what orders (if any) would there be overlap in the observed spectrum? Does your answer depend on the s+anb+a k;7jvb lit spacing?

Why are interference fringes noticeable q e;gb60 fjv0(cmv x.nonly for a thin film like a soap bubble and not for a thix6j;b(cve 0f.v 0nmgqck piece of glass, say?

When a compact disk (CD) is held at an a 8g eu+:a6g4;qpsff6mpk h 0qpngle in white light, the reflected light is a full spectrum (Fig. 24–56). Explain. What would you expect to see if monochromatic light was 6qhuq pskg0:+ mp 6pa;e4f8 gfused?

Why are Newton’s rings (Fig.,:ho:a w rz8(rzl .lgw 24–31) closer together farther from the center?

Some coated lenses appear greenish yellow when seen by puy; c-gcb9d9 reflected light. What wavelengths do you suppose the coc9-uyp9 c ;dgbating is designed to transmit completely?

A drop of oil on a pond apps5 9hc0.ggaxr,wjo ,zears bright at its edges, where its thickness is much les. 5,asgx c0wgjo r,9hzs than the wavelengths of visible light. What can you say about the index of refraction of the oil?

What does polarization tell us about the nature of liloizz,z2.;hd zr1 ww*z50 vfv ght?

Explain the advantage of polarized sunglasses over normal tinted sunglasws qg-r1+gbihx9:s tero/.n s3a:osd-a;/hxses.

How can you tell if a pair of sunglasseshg,e 8 - 6qhfd;imwe m7yk*s2cln;l1d is polarizing or not?

Two polarized sheets rotated at an angle of jq,ws) 9d1s8d /ef8o v+zaf tu90$^{\circ}\,$ 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 no atmosc*e8 unqef /3d7i rersi82i+a phere?

If the Earth’s atmosphere were 50 times denser than3njes()c: mnm it is, would sunlight still be white, or would it be some other co 3) je:(cnmnsmlor?

  Monochromatic light falling on two slits 0.016 mm apart producc,gixy/4wkr4tt0 m*l w.g g z.es the fifth-order fringe at anwxw, 4tkmgy4 c.l *g0/zritg. 8.8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of hy*1wc fljkh+nr5 bjk7 9 f04j 6gqvs,610 nm light is observed at an angle of 18$^{\circ}\,$ when the light falls on two narrow slits. How far apart are the slits?    $\mu m$

  Monochromatic light falls on two v 3ei +m)z+lo+q kwigw42z1wk qery narrow slits 0.048 mm apart. Successive fringes on a screen 5.00 m away are 6.5 cmqi+w 3kgkzz1wmw+oe)li 2 4 +q apart near the center of the pattern. Determine the wavelength and frequency of the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of light from a He-Ne laser, wilvu wsl1r,yo(ko f 3*k+fy xhz+)g. 5,rirv:cth a wavelength 656 nm, falls on tvwzrk.ri+,r+(o)*f5ko sfl:lc, h 1 yuxvg y 3wo very narrow slits 0.060 mm apart. How far apart are the fringes in the center of the pattern on a screen 3.6 m away?    cm

  Light of wavelength 680+izegbd,9;,gv+ts dv9s dmitcdg 6i-0ja) x . nm falls on two slits and produces an interference pattern in which the four m,; jsgvtgb +0 i,dz9dx6)cdv e9i +gai.d-stth-order fringe is 38 mm from the central fringe on a screen 2.0 m away. What is the separation of the two slits?    mm

  If 720-nm and 660-nm ligh9s;y c7 am6/,iwswc gq5dn )got passes through two slits 0.58 mm apart, how far apartggs , w)dq o;/cn5 y7i96wscma are the second-order fringes for these two wavelengths on a screen 1.0 m away?    mm

  In a double-slit experiment, it is found that blue light 6fd f w3v/(qaxof wavelength 460 nm gives a second-order maximum at a certain location on the screen. What wavelength of visible ligf f63/v( dwaqxht would have a minimum at the same location?    nm

Water waves having parallel crests 2.5 cm apart pass through 17baj1.(k x7oha zyfl4lz gn3two openings 5.0 cm apart in a board. At a point 2.0 m bazlgfx7 41jho3.nza7 1b l yk(eyond the board, at what angle relative to the “straight-through” direction would there be little or no wave action?

Suppose a thin piece of glass is placed in front of the lower slitgl: q.kin r 5cw)bdx3xva :-3x in Fig. 24–7 so that the two waves enter thew:rcx) adxvk-5 3: q lingx.b3 slits 180$^{\circ}\,$ out of phase (Fig. 24–57). Describe in detail the interference pattern on the screen.
24-7
24-57

  In a double-slit experiment, the third-order maximum for light of wavelmw8 :cyc.rk jf1t5.r xength 500 nm is located 12 mm from the central bright spot on a screen rt.m xfrc 81w5jy kc:.1.6 m from the slits. Light of wavelength 650 nm is then projected through the same slits. How far from the central bright spot will the second-order maximum of this light be located?    mm

  Two narrow slits separated by 1.0 mm are illx1*4x( e vq h2xabfvo/uminated by 544 nm light. Find the distance between adjacent bright fringes on a screen 5.0 m from the4b(xo/e x a*xv12vfq h slits.    mm

  Light of wavelength 480 nm in air falls on two sp+-7uqrp b5b qlits $6.00 \times10^{-2 }\;mm$ 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 (nj3h nh . c;g32yw7ey j -wq)jrhl36geh=1.60) covers one slit of a double-slit apparatus illuminated by 640-nm light. The centeryq 33jeg gjhhr;l- 63h.7n2jew)ywc h point on the screen, instead of being a maximum, is dark. What is the (minimum) thickness of the plastic?    nm

  By what percent, approximately, do ): hytl k0nby+:eac.g;n7fkxes the speed of red light (700 nm) exceed that of violet light (400 nm) in silicate flint glass? (See Fig. 24–14.) nty7:+ck.fx)ka0;yn:be l h g    %

  A light beam strikes a piece of glass at a )o )ms9y+-mnf-c elu s60.00$^{\circ}\,$ 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 contaiv q5*4 r,m jjv9axuy5vning two wavelengths, $\lambda_1\;=\;450\;nm$ 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 wide, what is tqn + 2;esaps.1nq3-h)nugyo ehe full angular width of the central diffractipen)nns3+2uahs 1ge;. o qy-qon peak?    $^{\circ}\,$

  Monochromatic light falls on a slit th. k2m32tubnrjat 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 7y eefd9/wmp .nm falls on 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 light. What + y*s l:o lzg7jq)9pgmis the width of the central 79l)syl * zpog:jmq+gmaximum (in cm) in the diffraction pattern on a screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm falls on a slm+31y/syf1rm rw ,bsm it. If the angle between the first bright fw/ybyrmsm3sr+1 fm1 , ringes on either side of the central maximum is 32$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central di2up9vo:+)u oit qc 2bmffraction peak on a screen 2.30 m behind a 0.0348-mm-wide slit illuminated by 589-nm lig)t:mciup2obu q vo9 2+ht?    cm

  When blue light of wavelength 440 nm falls on a single slit, the firsjya cp6ns; -p4dt; 80nqdgu qx/a a.v3t dark bands on eithevjupqqn -a0.d 3 ga;ady6 c;4s/ 8pxtnr 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 /;x-e s-amfw erfd7i8creates a central diffraction peak that is 9.20 cm wide on a sc87/wx sedra;-fmei- freen that is 2.55 m away. How wide is the slit?    mm

  If a slit diffracts 65i d5k-qdl33g gnjm3h5 50ua; xzxepa /0-nm light so that the 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 wavelength 420 nmz/x0;m53l ipgxaekd h35qdg 3njua5-?    cm

For a given wavelength li lvzx p/fo,82p:msdd85* kmdwa5t( $\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm light produce a secondzmxqgo**e 7( n*c+ qfw-order maximum when falling on a grating who *7* oqg*(qe+wzfnm cxse 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 graty ws/ma;) slsiq++.a sing have if the third-order occurs at an 18.0)assmsa l+wq+;y .is/ $^{\circ}\,$ 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 f6k * l3n:oogvaalling on a diffraction grating is observed at a 15.5k*va6o lon 3g:$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction grating 6g dmr +t01da72whpb mhas $ 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 normally ozu utj s b8((9nxjpqm-0d 4s:12 pzyzxn 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 order th p 3p26bktsw6xegwuc7t7d9s +mxx++a at can be seen if a grating with 6000 lines per cm is illuminpsp67 dx+gxu+7t e +s2t3x6awcmb9kwated with 633-nm laser light? Assume normal incidence.   

  Two (and only two) full spectral orders can be seen on eio u+v+xhdqyt2n k vr9y4 aq6,/ther side of the central maximum when white light is sent through a diffraction grating. What is thxa t46,ky r2o 9qy+ v+dvhqu/ne maximum number of lines per cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containing wavelengths from 410 nm to 750 nm fallp6 a8rc upp-e15orof )s on a grating withp6 8fr)cppoe-oau 15 r $8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which prod+tru:s nra8mvqezc/(rh a-2:uces monochromatic light 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 spectrumyo;*. jj pp;s5/7prlp yxk y9u lines 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 ) p3sx)4le* uy;ch la0r hkfg8thspf hay380 lh4l e)rx) gu;c*ke center of the outer surface when 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 if the glass ikkf.w+ux* w3plates are each 26.5 cmuxiw 3k+.*fw k long?    cm

  What is the smallest thickness of a soap fi+sx0u r*w8rgegui(:mlm $(n\;=\;1.42)$ 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 yellow (:fw;4nv6m zrs$\lambda\;=\;570\;mm$ 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 (not counting the2m)iiu. *mp9(k yigj x dark spot at the center) are observed wheipyixjgkim) .(29* umn 550-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 z p aa+syh;dcg7::e 1jone end of two pieces of optically flat glass, as in Fig. 24–33. When light of wavelength 670 nm is incident normally, 28 dark lines are observed (with one at each end). Howaas7cg h;:1z+:pdjy e thick is the foil?    $\mu m$

  How thick (minimum) should the air layer be between d*hnw+-dx8i- x (vccn two flat glass surfaces if the glass is to appear brig w8h dcv i+nn-xdx*(-cht when 450-nm light is incident normally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, suspected of being a sagajqmp.-da59 3g- )yux2 ca ftolen 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 alcohol ea4kww k5h.cs 3 z1yh..j9hzcz 8 s9ly$(n=1.36)$ 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 immersed in a cm8wkqba9-g +liquid, the diameter of the eighth dark ring decreases from 2.92 cm to 2.-+9 abkgc w8qm48 cm. What is the refractive index of the liquid?   

  What is the wavelength of the light entering an interferometer if 644 brig ouo w1:c;ts*pht fringes are counted when the movable mirror moves 0.225 mm:* 1o;ctpwso u?    nm

  A micrometer is connected to the movable mirror of an interferometer. When tk11x9hg k +nyyq)qb e1he micrometer is tightened)yqh 9 1nkbeqk1x1yg + 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 mirr*d ynw0j0z- kuor $M_1$ 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 interferoh * bjs2 s+repwit:34ometer (Fig. 24–59) passes through a small glass container containing a cavity 1.30 cm deep. When a gas is allowed to2p :sot34rie+jhs*bw 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 gas, assuming that the interferometer is in vacuum. $n_{gas}$

  

  Two polarizers are orienbr;j5b y6(g x:r3zyw4t,*jmd(bu vm eted at 65$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s angle for88zzxitto;wselq86 viq csi+98 ;ti , an air–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submerged in water if t x0(ltc.mo3 5kilj7 cthe light is hitting the di0kl(jcttio 75xm c3l .amond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so tcl;*h3 f xqcd7hat the light passing through them is a maximum. At what angle should one o*hdfc; 3lxcq7 f them be placed so that the intensity is subsequently reduced by half?    $^{\circ}\,$

  At what angle should the axes o ::mqztunpq6: f two Polaroids be placed so as to reduce the intensity of the incident mn:uz:p6qq:t unpolarized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are oriented o30 kcfjlr;n3l bw.cgb a 75v*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 at 38.0 b :4/zwee53z-oe pvcx$^{\circ}\,$ 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 b cda-w0 .7csmhe for reflections off the surface of water for light coming from beneath the surface? Compare to the angle for total internal reflection, and to Brewster’s whca s-c. m07dangle 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 Polaroid shel818ke ok-mq nets, each of whose aqmnkk88 -1ol exis makes a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength v5s3rmoqoi9vc9f 3/c$ 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 waves reflecting from mountains c7n;y7y z 2peb)wod.,(z1afswm9 qdcor airplanes can interfere with the direct signal frod,)7 d9m7b2pfnww y .cyoceq(; 1sazzm 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 source+zs;w8bk v i3ez5c1 wes passes through a diffraction grating with 8+i5wv c;1 zbkew3sez$ 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 through two narrow+-ffod*wc/n22a+02tpzticgeo ih * q slits 0.60 mm apart. The screen is 1.70 m away. A sco fo dw*pq2t2 ah2ci0- *i t/+zne+fgecond source of unknown wavelength produces its second-order fringe 1.33 mm closer to the central maximum than the 590-nm light. What is the wavelength of the unknown light? $\lambda_2$    nm

A radio station operating at 102.1 MHz broadcasts from two identicak*n b 48uml-itf pk7 vuf;b:;al 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 extend7- b *t uki;fkln:uvab f8m;4ping horizontally in both directions. 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 back from an outside doorway 0.88 m wide, ang()yntw ts3m kz,v944wz5hm w d blows a whistle of frequency 750 Hz. Ignoring reflections, estimate at what angle(s) it is not possible to hear 4v(zytk s9mgt5ww3,nzh 4mw) the whistle clearly on the playground outside the doorway.    $^{\circ}\,$ either side of the normal.

If parallel light falls on a single slilsu*vsm b8yi41v( m)ko);q 0w4iut hft of width D at a 30$^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain beetle hab;+ 3mn ,z1t1eiydoslve 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 angle of ten31+1 si;lmdbozy , 51$^{\circ}\,$. How far apart are the lines?    nm

  How many lines per centimeter must a grating have if there is to be no second-orels/7:j ;s7s2g cjtct der spectrum for any visible waveleng; jle7tcj/:7s c2tssgth?   $ lines/cm$

Show that the second- and third-order spectra of white light producorc rnjru t u+5)h/b;w:4(odled by a diffraction grating always:hnj;ocr/d4u orb(r u l+5w t) overlap. What wavelengths overlap exactly?

  When yellow sodium light3j;t hc19qh(wsailxjuo* -+ r, $\lambda\;=\;$ 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 grating with and thep vc1j *aj*uwxxh954 j pattern is viewed on a screen 2.5 m from the grating. The incident light4jw c auh1xj xjv*5*p9 beam consists of two wavelengths, $\lambda_1\;=\; 4.6\times10^{ -7}\;m$ 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 1dg wyjx-9e+ +7ekog a,50 nm thickness of it, when laid on glass, is needed to reduce refloy+ x d+jke7awg,9 -egection to nearly zero when light of 600 nm is incident normally upon it? Do you have a choice for an answer?

  Monochromatic light of variable wavelength +5 v.1:k:p atfgoz:nkl:xbez is incident normally on a thin sheet of plastic film in an:x5 ok: atfg:kz 1:.l+vebpzir. 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 an anti-reflective co*lb6* (npd nhfating $(n=1.38)$ 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 air layer between two flat ))huwy mv e7v6800i* ordln q;;q1pt0xtbuamglass surfaces if the glass is to appehm8q6nv;rmwve1)*0q )t yuixd0 ;ub0 l o ta7par dark when 640-nm light is incident normally?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the light tran(jdp9,fsjqrv ahsnl(e50 (u4smitted through a thin film layered on a flat piece of glass. Draw a diagram, similar to Fig. 24–30 or 24–36, and dej( p4j nlsa5qf0u(dhvs(r, 9 escribe the conditions required for 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 tnkqocfq juq5q* 2 du8((: ygo+he horizon is the Sun when light reflecting off a smooth lake is polarized mod*qo5:y q+ q(k jfou q2(cg8unst strongly?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as to reducec1/yic lt.efq ,,2lah the intensity of the incident unpolarized light by an additional factor (after the first Pyq h 2ta ,lefl,1/i.ccolaroid cuts it in half) of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light fall yx1dmt6lnutb(,k 79vi85 dlys on two polarizer sheets whose transmission axes are at right angles. A third polarizer is placed between the first two so that its69n781v myulklytb x (d5i, dt axis makes 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 c:rk4m)gu*o g placed in succession with their axes 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 througy+ orkd3gh 7t8h 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 lik+dg3hyt r78o ght of a He-Ne laser). Estimate the width of the beam when it reaches the Moon.    km

  A series of polarizers are each e8 n0axx (rk yx,c,8ji6wl/fjplaced 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 1dm-/e)8 v; kik blwpt$(n=1.34)$ 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 radiating 6.0-MHz radio waves isq3gnzc j-h g : .agvidbjrt4-0c )5q.n phase with each other. They are located v5icgq .gsn:rb04zd-j3q t. )h- acj gat points $S_1$ 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 contana+o x:1.eym lau*k8 bs:jh9v ining two wavelengths, 420 nm and 650 nm, enters a silicate flint glass equilateral prism (+k8vn hy9 bj::.a a1eomx s*ulFig. 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 and one wit5 zoscotk.4riu 0o,:r:g(m v mh $R\;=\;18.4\,cm$ 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