Does Huygens’ principle apply to sound waves? To water waves? Explainbsnu22p7ca 59ype+siv7 0qa n.

What is the evidence that lig ;; 2i+qhqpnwxht is energy?

Why is light sometimes described as7krqudaw 0q8so0cm+- 8sh . uj rays and sometimes as waves?

We can hear sounds around corners, but we cannot 6g(,1bhspj3unj v 8gcsee around corners; yet both sougb16js u hg,8c( n3pjvnd and light are waves. Explain the difference.

If Young’s double-slit experimentt ;y osyek)vw9yn d-buq0 x(52odz qp:+u0wh - were submerged in water, how would the fringe patternhe0q 0by o )zv o-n-dt;5+2yw: upx(kqudswy9 be changed?

Monochromatic red light is incident on a double slit, and the inte2ejux;e6h pr,vg s*4lrference pattern is view ;vh *jprxl6s4,2eueg ed on a screen some distance away. 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 interfereovb 9kh i*w4gm y d1ciy- -kdd88/io:z if their path lengths differ by h4/o zg1kkhoy8cyd-ivb- d :9diimw*8ow much?

Why was the observat /as : wu7rkx1aks vy0g4,tks/ion of the double-slit interference pattern more convincing evidence for the wave theory of lig akt k:4kvssua1/ s/r, w0gy7xht than the observation of diffraction?

Compare a double-slit experiment for sound waves to that for light wavdt ;n3(l dm(dtes. Discuss the similarities andddtm; t(l3 (nd differences.

Why doesn’t the light from the two headlights of a distant car prod+hzsajlq9wsaznzp /wk8 n) jteb2k m +;+6 6f1uce an interference fl za+w6bzksn wnk/+m6;9 j+qph 2s z1)ejat8pattern?

Suppose white light falls on the tb8t q: ge4qqfvf/q lc8p45 w*dwo slits of Fig. 24–7, but one slit is covered by a red filter (700 nm) and the other by a blue filter (450 nm). Describe the pattern on the screen. l 4qg*cde4qqb8:pvf5wft/ q8

When white light passes throuwq+z*47x3epg oyihp:gh a flat piece of window glass, it is not broken down into colors as it is by a p+xe: w*hpqoi4gyp 3 z7rism. Explain.

For both converging and diverging lenses, discxqly0 /ft;lv om.- k.vuss how the focal length for red light differs from that for violet light o lvmy-tv;ql/k0f.x..

A ray of light is refracted through three diffejgi(u/aj xdw,d(d 1+ qrent materials (Fig. 24–55). Rank the materials accor+xi(d/ au1d (jgqj dw,ding to their index of refraction, least to greatest.

Hold one hand close to your eye and focus on a distant light so9 y9 nx*e1oin vakg57a l*tbj0iz9xu1urce through a narrow slit between two fingers. (Adjust your fingers to obtain the best pattern.) Describe the pattey9x1z5jaoa 0x g7 ben9v 9uli*i t*n1krn that you see.

What happens to the dif,cf+yszv-.t2w z wt v9fraction pattern of a single slit if the whole apparatus is immersed in (a) water, (b) a vacuum, instead of 2sz+z wt,t9. vyw-vcfin air.

For diffraction by a single slit, what is the eff:sccxh2 m9ld; ect of increasing (a) the slit 2x9lm;c :cdhswidth, and (b) the wavelength?

What is the difference in taed :xc. h0b/v3h(g vk-ng 4wshe interference patterns formed (a) by two slits $^{-4}\;cm^2$ apart, (b) by a diffraction grating containing $10^4lines/cm$?

For a diffraction grats-zi l;bvn a4.ing, what is the advantage of (a) many slits, (b) closely spaceva libn.-4;s zd slits?

White light strikes (a) a diffraction grating, and (b) a prism. A rainbow wko j(5h9npy2ocids 8r6.qj2 appears on a wall just below the direction of theys .hp2o6o5 c2(qi8jwndrj9 k horizontal incident beam in each case. What is the color of the top of the rainbow in each case? Explain.

For light consisting of wavelengths between 400 nm and 700 nm, o 1s:g j2a3.*tsc r-1 qyuzicoincident normally on a diffraction grating, for what orders (if any) would there be overlap in the observed spectrs*jr yooq ug:1.cc-si31 taz2um? Does your answer depend on the slit spacing?

Why are interference fringes noticeable only for a thin film like a soap46,5u4q :ned9f.7h nit xf) 8z8hrvxcbag yjo bubble an9eqat d8ho h7v8yxgjub5nc fx.,i64r)f4: zn d not for a thick piece of glass, say?

When a compact disk (CD) is held at an angle in w c3y2t fpl dfuxmid0bu5h5.4+hite light, the reflected light is a full spectrum (Fig. 24–56). Explain. What would you expect to see if monochromatic light was used?ypu lf.3 2m 55f0i dcx+4bhudt

Why are Newton’s rings (Fi9dj3hlcq; ;jfg. 24–31) closer together farther from the center?

Some coated lenses app/ghy,0-9 izvr y ejl)pear greenish yellow when seen by reflected light. What wavelengths d9-hlzyg,ip0 ejr)yv /o you suppose the coating is designed to transmit completely?

A drop of oil on a pond appears bright at its edges, where its thickness is mu5 4oep joj2 3ls*,m9x ,fyghmbch lessho5 eysm2, j*xlo3,9bpjgf4m than the wavelengths of visible light. What can you say about the index of refraction of the oil?

What does polarization bl2;ktd w2s 9ptell us about the nature of light?

Explain the advantagy *vo o)1 +qo)ctsqa.ce of polarized sunglasses over normal tinted sunglasses.

How can you tell if azgb3jk 2+bguo(h; ;fm pair of sunglasses is polarizing or not?

Two polarized sheets d7k4x n34:ax0omf ts kcbna5 :*i *ntkrotated at an 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 +- mp6 umfvg8d99chme 9j dxv;sd.7yh of the sky if the Earth had no atmosphere?

If the Earth’s atmosphere were 50 times denser than it is, woud89+rhg qum7 va6o*e jld sunlight still be white, or would it be a mr6+*o7hdqe uj9vg8some other color?

  Monochromatic light fz f7h tzfu l;l*h629)e6dx zisalling on two slits 0.016 mm apart produces the fifth-order fr)z9dfzxf;u26zes t l hh7* 6liinge at an 8.8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe lmfqc9m nwv:2 t.7)w8nqx +otof 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 lb1-qlf t y,/hvery narrow slits 0.048 mm apart. Successive fringes on a screen 5.00 m away are 6.5 cm apart near the center of the pattern. Determine the wavelbl,tlh yq1/-fength and frequency of the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of lil gxc;p.t*s8jykw y3 6ght from a He-Ne laser, with a wavelength 656 nm, falls on two very narrow slits 0.060 mm apartwsy;l*k j t8 p.6gy3xc. 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 and produc./pr l jndq6-d 8lrwc2es an interference pattern in which the fourth-order fringe is 38 mm from the central fringe r n2lwr d8j.6pqd/- clon a screen 2.0 m away. What is the separation of the two slits?    mm

  If 720-nm and 660-nm light passes through two slits 0.5i+97vm6cgi -fqe6x hz 8 mm apart, how far apart are the second-order fringes for these two wavelengths on a screen 1.0 mzehc6g xq9f 7ii6m+ v- away?    mm

  In a double-slit experiment, it is found that blue liji9)e0- b/c oo9nq.cshiu8fv ght of wavelength 460 nm gives a second-order maximum at a certain location on the screen. What wavelengt0.ob98fjvconc) /-9iqih esu h of visible light would have a minimum at the same location?    nm

Water waves having parallel crests (n, 0mqchiy5g.al+ wk2.5 cm apart pass through two openings 5.0 cm apart ing.,( in+cwly5 ahkq0m a board. 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 glass is placed in front of the low berxmibl-4hf:kxwg ,8 (nvbd 1* qz-8er slit in Fig. 24–7 so thvew-(krxzi*d 8b 4mg:l h8fb1q,x b-nat the two waves enter the 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 experime0um1cu.iz xx *-7slp 6s3e aeent, 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 mez. us7a 1 euies*3 xp-6x0lcthe 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 ill/lxc3qs) sxac p:a o(a.2 :sgguminated by 544 nm light. Find the distag(:x x:3la /c spaqga s2o.c)snce between adjacent bright fringes on a screen 5.0 m from the slits.    mm

  Light of wavelength 480 nm in air falcq 8usu8um akb7lny* 4re,5 4uls on two slits $6.00 \times10^{-2 }\;mm$ 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 plasticq umj7jzm92op zcl 395 (n=1.60) covers one slit of a double-slit apparatus illuminated by 640jp39zm27ljqo5um9 c z-nm light. The center point on the screen, instead of being a maximum, is dark. What is the (minimum) thickness of the plastic?    nm

  By what percent, approximately, does the speed of red light (700 dx/m(/0m nm5xy2z8m uu*weq cnm) exceed that of violet light (4xqz8m cxud* m/emmy(n 0w2/ 5u00 nm) in silicate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece of glass fzuknc*3 v ,i3at 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 t 4c.;igkq/1 es8.pi( jaukd eowo 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 widldrsa7x5g t5 5e, what is the full angular width of the central diff la7 s5gdrx5t5raction peak?    $^{\circ}\,$

  Monochromatic light falls on a slit kw8g6sk 7n8kegjn +8gthat 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 fallsx e6d2et-y.ig 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 is the width of tjhsg e 3j;jjw d-/qv99he central maximum (in /jjgjs;v9 - hdj9wq3e cm) in the diffraction pattern on a screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm falls on a slit. If the angle betweg.q /y *gwlds co+8gsr4ng9u3en the first bright fringes on either side of the central maximum is 32wd 9. gs s+gcunq/38glo*yrg4$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central diffractii k0-f*2ucnto o(r3ox on peak on a screen 2.30 m behind a 0.0348-mm-wide s-fo(nc tr2*u3oox 0iklit illuminated by 589-nm light?    cm

  When blue light of wavelength 440 nm falls on a singz/ ) uzwq9a4s+qk7py w4vn0ejle slit, the first dark bands on either side of center are separated by uk+z7w 9/eaw4szqy4vj pq) 0n 55.0$^{\circ}\,$. Determine the width of the slit.    $ \times10^{-7 }\;m$

  When violet light of wavelength 415 nm falls on a sing*5h 0.cg8tdy-x doy4tk s 5jirle slit, it creates a central diffraction peak that is 9.20 cm wide on a screen that d85js oy4r-h5.0kxidtgcty* is 2.55 m away. How wide is the slit?    mm

  If a slit diffracts 650-nm light so that the diffraction maximum is 5 5mk70 pld106ih hm/.nx3sjcdsfeiw4.0 cm wide on a screen 1.50 m awayms6sed5hkdi005 fpiw mj37 .1cxhl/n , what will be the width of the diffraction maximum for light of wavelength 420 nm?    cm

For a given wavelength jn2 +.rt 9issij7q3/pbmibn9 $\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm light produl) bjlo9c zfa9;jl 1l52-zj:d tz +odoce a second-order maximum when falling on a ) j5z :c ot z2 ll19-ba;olo9djzj+dflgrating whose 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 cn,+ i27q hfpithird-order occurs at a+,hip fi7cq n2n 18.0$^{\circ}\,$ 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 l xc4wnod ulel/qp -. s8o,fx44;kxd h*ight falling on a diffraction grating is observed a8k , ho.uf /l ;xl4soc*4qxex dp4wn-dt 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 c-0k fug4vl*i- i/n8nxi2 jvb has $ 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 oqgciv9ngx-9 6 n 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 that can be mp81boof6d u/ati r74f-,ab b seen if a grating with 6000 lines per cm is illuminated with 633-nm laser light? Assume normal incidence1poboi, r-u maf f6d8/t4b7ba.   

  Two (and only two) full spectral orders can be see quuchr*o9 * cut21-hrn on either side of the central maximum when white light is sent through a diffraction go2t hhc9 q ucuu1**-rrrating. 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 nm x 5pgcxwu+ lsx)m7+:l x0 ta7xfalls on a grating with )mc++x05xwt7sglpluxa: x7 x $8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which produces monochromatic light of a known (mlem 1.xort*0 egl3 owavelength $\lambda\;=\;6.328\times10^{-7 }\;m$ 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 lines ap8 x4t 50urpy1wf:n-cdam o:v re 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 rd(l lvt/r85(5cd s )h05g -b ubbmbtineflected at the center of the outer surface when illuminated normally by white light? Assume that c)5d-d lg(bmt5/nsbb bh 5(vult0r8i$n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the dark fringes in Example t jz)yxv,7d x024–8 if the glass plates are each 26.5 tjv,zyd)0xx 7cm long?    cm

  What is the smallest thickness of a soapi 42zq,s0f/jza ,ik la 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 yellow (,b -izm lqt/bdgwm1 -4$\lambda\;=\;570\;mm$ 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 ;lu+ nyhzko s)+sxxc. mu2dox76/- asand 31 dark Newton’s rings (not counting the dark spot at the center) are observed when 550-nm light falls normally on a planoconvex lens resting on a flmcx+)s / oy os2x+nas.uxd; kul-h7z6at glass surface (Fig. 24–31). How much thicker is the center than the edges?    $\mu m$

  A fine metal foil separates o 3o;3z8oqc yyv+gwt3d ne 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). How thick is thvy3g otw;+qo8z c3d3 ye foil?    $\mu m$

  How thick (minimum) should the air lzhowh(kb4f w5w nl 1y8o64vk2ayer be between two flat glass surfaces if the glass isbk6 ok8nw4h4h5w1y o wlfv 2z( to appear bright 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 svna:qk5z a5i7 tolen 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( 7 g x (d0nal:vop6xsrk+e2pc $(n=1.36)$ 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 liquid, tj5vv6o3c2)ya9os bd q o6 q1jshe diameter of the eighth dark ring decreases from 2.q9ao2d65 qjs jvb63cvs)oy o1 92 cm to 2.48 cm. What is the refractive index of the liquid?   

  What is the wavelength of the light entering an interfn1 xefc/( (wdjerometer if 644 bright fringes are counted when the movable mirror moves n ejwcx1(/f(d 0.225 mm?    nm

  A micrometer is connected t4)ykq0wn (odd68cpz ro the movable mirror of an interferometer. When the micrometer is tightened 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 wave k orwp)cdd80ny(zq64length of light used is 589 nm.    $\mu m$

  How far must the mirr4 j8:zjx -bx2o .dwwjlor $M_1$ 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 inte lpj*zihw6k/vm8(l r 7rferometer (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 gas, assuming that the inth* lil/wpvrk j87m( z6erferometer is in vacuum. $n_{gas}$

  

  Two polarizers are oriented at 65nh- o6 qa5k0gn$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s angle for an air–glas83s/udn (b b-gy)boqns $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submerged in water if the light i8p8xv (lem( igs hitting theplgvmx((8 i8 e diamond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the light passing through 4wm 8h/*eeoo athem is a maximum. At what angle should one of them be place/ hm8eo*eoa w4d so that the intensity is subsequently reduced by half?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as tw i+a)tz i+ le*iso-/to reduce the intensity of the inciden+swoa te/iztii +l) *-t unpolarized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are orienteldo: 5xu42 h-, jrj*7zyx3um ai*ldte d 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 oriw7n 5i6q;m-byjd1) ur +tu vciented at 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 reflections ofb8s. cs9)g* woqvonj/f the surface of water for light coming from beneath the surface? Compare to the angle for total internal reflection, and to Brewster’s angle from above cj9ssobwnv*)8 g ./oq 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 successigkslpy *s d ll5kz,mitba24 s)3g);:mve Polaroid sheets, each of whose axis makesk,sg yaig35 :lstk4l) )mp*2lbmsz ;d a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength w) -ka *jxv7nk.h 3ushch7jm+$ 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 mount yna+, ;d)oiuvg xb q;yis;:8yains or airplanes can interfere with the direct signal from the sty x;d+:gysv b;o qnuia;,8)i yation.
(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 sources pa3;l s+yfrf c92 hfd :4pb0ap p:pd.xjwsses through a diffraction grating with lj:pf rc42h+ xd.b;9w:f0aps f3yp d p$ 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 spp23 )ezg aft*lits 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. What2*agf ) p3etzp is the wavelength of the unknown light? $\lambda_2$    nm

A radio station operating at 102.1 MHz broadc2u piorzi*+ uo(zno/ xup* c5:asts 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 ep: ui c* oz5nip/ uux2*oo(z+rxtending 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 out/wc3o i0wqk h;side doorway 0.88 m wide, and blows a whistle of frequency 750 Hz. Ignoring reflections, eckww q oih03/;stimate at what angle(s) it is not possible to hear the whistle clearly on the playground outside the doorway.    $^{\circ}\,$ either side of the normal.

If parallel light falls on a single slit of width D at a 30h 4phe:6zv5iqe(okqx(- l5+zgo )tet $^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain beetle have a series of parallel lines across them. When t- ri.uus 3cu9a 5j8l/is2hdznormally incident 460-nm light is reflected from the wing,sl3a ti.cd-9h 5/r82z uiuusj the wing appears bright when viewed at an angle of 51$^{\circ}\,$. How far apart are the lines?    nm

  How many lines per centimetrgnv) 0n:0tth na6b7xdv/6pz5u ebl(er must a grating have if there is to be no second-order sla nn d6tvxt7 v)eup00z(r:6h n 5b/bgpectrum for any visible wavelength?   $ lines/cm$

Show that the second- and third-order spectra of white light producedoqazqgh8 a, h+q)6 y)z by a diffraction grating always overlap. What wavelengths overlap exactly6+ayz g h)q)qo ,ahz8q?

  When yellow sodium lighotp2 u+*c.0zunkoa): k jbd:tt, $\lambda\;=\;$ 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 the pattern is 4y3m(si8 9 d3ay kytljviewed on a screen 2.5 m from 4(si3 yjat89ymyk l3d the grating. The incident light 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 refractiongo+,; v7o j- )kvnrd4xsdly9v of a clear material if a minimum of 150 nm thickness of it, when laid on glass, is needed to reduce reflection to nearly zero when light ods9xl o +yvd74krv,;) -jgvnof 600 nm is incident normally upon it? Do you have a choice for an answer?

  Monochromatic light of variable wavelength is incident noaz xzo2)y)uq 7rmally on a thin sheet of plastic film in 2)a 7uyxzzoq)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 nxp3f23j j- euneeded for an 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-zeroq4kcphw05k p5) thickness for the air layer between two flat glass surfaces if the glass is to appp ck w4q5k0hp5ear dark when 640-nm light is incident normally?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the light transmitted through a tx1 h-b l1pvp.khin film layered on a flat piece of glass. Draw a diagrphkb.l-xpv1 1 am, similar to Fig. 24–30 or 24–36, and describe 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 the horizon ilv4q,;rv j g.ztqa13qs the Sun when light reflecting off a smooth lake is polarizev13lqq j,g aqv. z;rt4d most strongly?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as to reduce tux7 * nwu5eo;nhe intensity of the incident unpolarized light by an additional faco n5x7nuw ;e*utor (after the first Polaroid cuts it in half) of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light falls on two polarizer sheets whose transmissf644(q sw)ve-q u f5qyuqu7j2rjage) ion axes are at right anglesr(s evjq42 quqfj7y4 u6-5))gaq efwu. A third polarizer is placed between the first two so that its 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 placed in succession with their axes vev fe7 yyviu69fsl6 +(k/hvf0 drtical, 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 through a slit of width 1.0 3a w3uw. b8 yt4zqy lhns0s-;fcm and is pointed at the Moon, whichw0q3ny.3 fwu-z4th ;as8slby 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 reaches the Moon.    km

  A series of polarizers are each placeomxyx/ 0/gqg5iy2w6h6 0cn sxd 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 5x5 w978vl ops)a:cyydy9fjs$(n=1.34)$ 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 radiae fr32 sh.pb/gting 6.0-MHz radio waves in phase with each other. They are lochr.g/ fpeb3s 2ated at 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 containing two wurn e)q9l:8i)ib1z2 agg ( zyoavelengths, 420 nm and 650 nm, enters a silicate flint glass equilateral prism ( a)uqr iyz9i znelb(g:8g)o21Fig. 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 an7atv017anz wa9pomnw 23 +n surface and 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