Does Huygens’ principle apply to sound waves? v msi4mts ;sx dy:35rov+o k9k ;r0(mtTo water waves? Explain.

What is the evidence thhazk ,xhz gn5g3*,,lwat light is energy?

Why is light sometimes described as rays and sometid0*:8fnlld p hmes as waves?

We can hear sounds around corners, but2(oi3dmwk o3)mefx + q we cannot see around corners; yet both sound and light areo+3e3 dqko mwim(xf2 ) waves. Explain the difference.

If Young’s double-slit experiment were submerged iw;c,:d k-dkvwo8a5uovjq;/vmixb 2 9 o zy0w(n water, how would the fringe pattern be c:/ ,28mw; kwvx (cv0 jzddok;5 ibwyu9-oq aovhanged?

Monochromatic red light is xwtne0ja0f (i 9egr *0incident on a double slit, and the interference pattern is viewed on a screen some distance away. Explain how the fringe pattern would change if the red light source is*i0ee9n0 f( t0rg jawx replaced by a blue light source.

Two rays of light from the same source+bnok2l 2;q ls j:lvi+ destructively interfere if their path lengths differ by how mb ;sv2 l2qojnk:++lliuch?

Why was the observation of the doubi1nh r:d;9*o mthbn0ple-slit interference pattern more convincing evidence for the wave theory of light than the obse oitnnm;d* 0rhh: 9pb1rvation of diffraction?

Compare a double-slit experiment for sound waves to that for light 1ziopw+y 6; xdb8s* xrwaves. Discuss the similarities and differencesxw o1b+zi6d8*pxr ;ys.

Why doesn’t the light from the two q69pm1*vl vpx* : k/dabo.nnc3wg pm2headlights of a distant car produce an interference patter9pk* 3wqx.v:da2mcb*m n1/n p6g vplon?

Suppose white light falls on.8n(k 5wpqy gu the two 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 op g 8(qu5ky.wnn the screen.

When white light passes te .;.7ubn 7j6j pkvmuhhrough a flat piece of window glass, it is not broken down into colors as it is by a prism. Explaib;epj7hjn 7.v uum6 k.n.

For both converging and dv/(yb4 b2u .krbwuh2v iverging lenses, discuss how the focal length for red light d wrb 2v24v(/ukbuby.hiffers from that for violet light.

A ray of light is refracted through three different r efb+5 m*3tpgmaterials (Fig. 24–55). Rank the materials according to their index of refraction, l+b fregp 3m5*teast to greatest.

Hold one hand close to your f cqwzzl348wj*wznw o ij6 )1:eye and focus on a distant light source through a narrow slit between two fingers. (Adjust your6: zfon 1wjj*wi)83 w4zlqc zw fingers to obtain the best pattern.) Describe the pattern that you see.

What happens to the diffraction 3 xd 1lbe2gkd)pattern of a single slit if the whole apparatus is immersed in (a))g kl21bdxed3 water, (b) a vacuum, instead of in air.

For diffraction by a single slit, what is the e 2bb;a4dku(:ci vhef: ffect of increasing (a) the slit widthaf;(e: 4kc: bdu2vhib , and (b) the wavelength?

What is the difference in the interference patterns formedl7 ;6lkqg a.r-klu(y j (a) by two slits $^{-4}\;cm^2$ apart, (b) by a diffraction grating containing $10^4lines/cm$?

For a diffraction gr. u/ ia,mgpfa +y(zg8aating, what is the advantage of (a) many slits, (b) closely paz/g8ag i.(a+ yfu,m spaced slits?

White light strikes (a) a diffraction grating, and (b) a prism. A jo66tzv/k,mu .ug (/xj knnn;rainbow appears on a wall just o/j(n6;ugkx /, u6vjtnm.nzk below the direction of the 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 400w, l0 1dya4ulz8e ;etx nm and 700 nm, incident normally on a diffraction grating, for what orders (if any) would there be o0ezeld, xw4 ul18ayt ;verlap in the observed spectrum? Does your answer depend on the slit spacing?

Why are interference fringes noticea n(byr n)q8u yn:xg(fr2m l+/zble only for a thin film like a soap bubble and not for a thick piec(y8qn)r nr:/2mb (yz u+ngxl fe of glass, say?

When a compact disk (Ckp7nos orl(o/3cu08p D) is held at an angle in white light, the reflected light is a full ssop37cp08 u(o/rl onkpectrum (Fig. 24–56). Explain. What would you expect to see if monochromatic light was used?

Why are Newton’s rings pw8fxpp 85ij :)qfmre f,q/2b (Fig. 24–31) closer together farther from the center?

Some coated lenses appear greenish yellow when seen by reflected light. What wavz5;jz1ydxz sz)j- /ccelengths do you suppose the coating is designed to transmit complez1z;ccj5xdzy j-/z ) stely?

A drop of oil on a pond appears ys+ j6;0j (dxw pr.uxdbright at its edges, where its thickness is much less than the wavelengths of visible light. What can you say about the index of refraction xxjj;+( p rd0.dw6usyof the oil?

What does polarization tel4l9ibh4 ;to x megjpj2fi73h4l us about the nature of light?

Explain the advantage of polarized sungl t ) pfq)f9u d l:aekg0:sj1:we+bx0zwasses over normal tinted sunglasses.

How can you tell if a pair of sunglasses is polav*,0om; jp rtcxq2 b+orizing or not?

Two polarized sheets rotate4j3/vf jd*-eni/6cb ty hh)evd 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 of the sky if the Eartu,drz/q tt)ss.z ok,6h had no atmosphere?

If the Earth’s atmosphere were 50 times d):j9 l2:wqzl fr y 2pq2mrx(gdenser than it is, would sunlight still be white, or would it be2 lr:2z9 pyr fqxm2dgw(qj) :l some other color?

  Monochromatic light hxs7,w*u c5xi0y;/cx, cz d xffalling on two slits 0.016 mm apart produces the fifth-order fringe at a* wsx0cc7;fzux ci5 /hyx,,xdn 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 angle. z(7mgvr- gde 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 0.048 mm apart.3oa /.5qf*lu 4hywk hi Successive fringes on a screen 5.00 m away are 6.5 cm apart neafhl.yu i*oahw4 5k/3q r 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-5pbk9s 4*af*z oh .jz4claq i+Ne laser, with a wavelength 656 nm, falls on two very n5*hi+9.lob acf4kp j qa*z zs4arrow 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 nm falls on two slits and produces an interfer6gwy;s29ervba -ajo/p)fd j6 ence pattern in which the fourth-order fringe is 38 mm from the central fringeb y -j;)a66rgwo p9ad2s/fv je on 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 sli7suxpw.9(xu--uqn ene.(x 2 sy 5kynqts 0.58 mm apart, how far apart are the second-order fringqexk5 wnsu 27..u p( y( nn-9yqxux-eses for these two wavelengths on a screen 1.0 m away?    mm

  In a double-slit experiment, i l2zs4u q)fzap 0e)mq)t is found that blue light of wavelength 460 nm gives a second-order maximum at a certain location on the screen. What wavelength of visible pqq)az z0 )s m)ul4fe2light would have a minimum at the same location?    nm

Water waves having parallel crests 2.5 cm apart pass through two openings 5.0 c cy7qcjaqp,+ e nj;2.im apart in a board. At a point 2.0 m beyond the board, at what angle relative to the “straighn7j,i q+jyp.cca2 eq ;t-through” direction would there be little or no wave action?

Suppose a thin piece of glass is placed in front of the l(wg pyj+ran. pw2t-r +yxu/i(ower slit in Fig. 24–7 so that /x-i+wgrt uyp(pn2 r+. j (awythe 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 experiment, the third-order maximum for li,dj*uubue0()zzpmk / n,xf( ight 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 proj,,mzb0zfp uj/eu ux(d(k ni *)ected 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 illuminated us**,z :p frtjdol. e)by 544 nm light. Find the distance between adjacent bright fringes onz,* ) u.toe f:dlsrp*j a screen 5.0 m from the slits.    mm

  Light of wavelength 480 nm in air fss4: / a,ahxbqalls 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 plastic (n=1.60) covers one slit of a double-slit ap fesx4wahutuh7b.4qq 0;; l7 vparatus illuminated by 640-nm light. The center point on the screen, instead of being a maximum, is dark. What is the (minimum) thickness ofvu;w4st7h7uqx he b 4;a.l fq0 the plastic?    nm

  By what percent, approximately, does the speed ofrt 4 xfrqgd7): red light (700 nm) exceed that of violxr4)td f:gq7ret light (400 nm) in silicate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece of glass at a 6dr89 jo1/ytvsb:gxxkcf8 i x6)j 2y-g 0.00$^{\circ}\,$ 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 con dpci1x,2egt, y)ut x3taining 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 s5mzn b+f) egv3lit 0.0440 mm wide, what is the full angular width of the central diffraction peak?+5nv 3fge bmz)    $^{\circ}\,$

  Monochromatic light falls on a slit t:;p wskovo a;88q5sf8 ur;jo rd9/znthat 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 o .,t70nrz kvhnqw74vjn 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 cl2mq .c.e.+ ac6assh illuminated by 450-nm light. What is the width of the central maximum6c.scsh+ q.m ec2 l.aa (in cm) in the diffraction pattern on a screen 5.0 m away?    cm

  Monochromatic light of wavelength 65nmf1s iw r+r.73 nm falls on a slit. If the angle between the first bright fringes on .f1s nr7+i wmreither side of the central maximum is 32$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central diffraction peak on a sc7bwil qy- bjn 1ods9o(rs9 g38reen 2.30 m behind a 0.0348-mm-wide slit owq9g(j93n 1sldysbo ib7-r8 illuminated by 589-nm light?    cm

  When blue light of wavelengthwe r39 s59jmux 440 nm falls on a single slit, the first dark bands on either side of center arr99x 5ew jsu3me 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 a2y7u(fr sjgq *vg59yn central diffraction peak that is 9.20 cm wide on a screen that is 2.55 m away. How 2j*sgfn7( y5q vuryg9 wide is the slit?    mm

  If a slit diffracts 650-nm light so that if4f zx/jx w6o3cj- mw d04x4ze: vm)sthe 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 nm? ijmwm4 x4 /f c0v: zozs wx43-x6f)dej   cm

For a given wavelengthgb( vtdjg0/u v 7)wpn0 $\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm light produce a second-order masb1e,)ox/a+xc wo8d bximum when falling on a grating who)/xbwosa+8 o,c xbd1ese 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-ory)c85/e fr/8uqtgj.iur f1zrder occurs at an 18j recqr/uuy1fz5r.t )if/g8 8.0$^{\circ}\,$ 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 58sb cr6(jq ck+im:n d-69-nm light falling on a diffraction grating is observed at a 16c(:c- q6 kr indmsjb+5.5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction gratin4tgm-x d2e f3.ml/adeg 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 normall.wl,sd dial 7-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 spectrnbyt2 j0(: 8u1wn cu :as8hroskxqp z2n4*0ukal order that can be seen if a grating with 6000 lines per cm is illuminated with 633-nm laser light? Assume normal incidence0ku hqu(b*nk4t082c:zy: n 8p uj1worsa 2xs n.   

  Two (and only two) full spectral orders can be seen on either side of t5we 2aw9;bplu he central maximum when white light isu5;2ebl 9pwwa 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 4 p:h8ml0- yndc*gvbt; rpot-7 q 5:dfn10 nm to 750 nm falls on a grating withl -pqftdcpbd0rn:*hyg o7:nv;- 5m8 t $8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which produce+sv (smp4z9gms 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 spectrum lines are measured by a g,je h(12c9n7q8:hctn pjz gq$9500-line/cm$ 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 12q by cu +sf 2(bwk)huyiwu2,x6uk4.7 e0 nm thick, what wavelength is most strongly reflected at the ce7 2f2,u4k(ie +k) sb. hcyquxwuuwy 6bnter 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 k1z*taso,qj 4 glass plates are each 26.5 cm long? 1so zqj4 t*k,a   cm

  What is the smallest thi-/ymos07v,m jhyz5 ;n qvp6nyckness of a 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 greenc rd*uq: j./ucqh+ hh/ish yellow ($\lambda\;=\;570\;mm$ 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 aiwe ly2 )9*w. )+ snl )xk)jltz3yzey); zoftznd 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 rexllw*tiy loetjf)z+)yz3) 2)ew.;) n y kzs9zsting 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 end of two pieces of optically flat glass,jck +s7- /zxqm as in Fig. 24–33. When light of wavelength 670 nm is incident normally, 28 dark7sqm k/-jc+ xz lines are observed (with one at each end). How thick is the foil?    $\mu m$

  How thick (minimum) should the air layer be benna sroy6 q:j8+;x+mctween two flat glass surfaces if the gl +oym68a+nn:js qcx;r ass is 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 ae7 g 0a7mokk. dbgpo9d)0hzj6 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 alcohol u:4 jud2cy*l ly/aw8b $(n=1.36)$ 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.c m s:uyqk,nf pb0.4v1xcw3t. 24–31) is immersed in a liquid, the diameter of the eighth dark ring:04sft, bymux1nkv3pq .c.wc decreases from 2.92 cm to 2.48 cm. What is the refractive index of the liquid?   

  What is the wavelength of the light entering an interferometer 7+lo4tar2g)k :kdy*u tt 7njb if 644 bright fringes are counted when the movable mikgd+ t)runjtl2 : ob4k7y7*a trror moves 0.225 mm?    nm

  A micrometer is connected to the movable mirror osynz3ab 4r ((/ai vkn5f an interferometer. When the micrometer is tightened down on a thin metal foil, the net number of bright fringes that move, compared to the empt( zak (3rvy/isbn5 na4y micrometer, is 272. What is the thickness of the foil? The wavelength of light used is 589 nm.    $\mu m$

  How far must the mirrom,9:wady yjgbc 8qnu. 5;cfl,r $M_1$ 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 (Fig. 24–59) passes thy (;flqpe y 0uv6aqtlh 0r+8z.rough 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 mov60(yp u0qlf8;atvqz. yhl r+ ee 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 oriented (ozs b7ld jt 8dnj:85jat 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–glass i: lg)yfu5cw-c k 88ep$(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submerged in water if the lih3u.q5 oz7:wel7icn u ght is hitting the di3w e5 7i uch:luqon.7zamond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the light passing through theheuro( 6e2 hz4m is a maximum. At what angle 6 2z4h ehur(eoshould one of them be placed so that the intensity is subsequently reduced by half?    $^{\circ}\,$

  At what angle should g1 f2as +vjplj)7ms2gthe axes of two Polaroids be placed so as to reduce the intensity of the incidenplv2 ) ajgf s1j72mg+st unpolarized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are ov d ;4 /d m3kkv)jtql5 b(mdeil3x(oh6riented 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 at9krhfzl20nvr7e3;6t3 ic xwj 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 off the sur66.41lndzey c e8d wm4l5mhpbface of water for light coming from beneath the surface? Com6bpcn8dwel.514ym6m l hze4 dpare 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 passez0-w zg0 o9/spo+xhp mf;;g/e/dbc n ks through five successive Polaroid sheets, each of whose axis makepxohk+pgbn / ;f/ 9-ose;zwgmdzc0/ 0s a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength s(w-w44 i ,cxwnhg e+e$ 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 or airplanes can intl8bl,e5o qzkgc:)+icerfere with the direct signal from the stationlgi,8 :l5 c z+ce)oqkb.
(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 separatez-. 6dv(jy ng eabi(8k sources passes through a diffraction grating with (z6.y - ed givjbnka8($ 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 a-(az bm3emz6d xa2u :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. What is the wavelength of the unknown lightba:m2ezaa m( ud6z-3x? $\lambda_2$    nm

A radio station operating bhf(ob)6eoafi ;. n7s 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 andbf7n)bosa.o h f6; i(e extending 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, and blows a whisisdii+vndx.6o3;qr /tle of frequency 750 Hz. Ignoring reflections, estimate at what angle(s) it is not possibl+oi/r6 disqxv d 3;.ine 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 y48zxbqgx.715ka vhq30$^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain beetle have a series of parallel lines acr 0 0cklju8 4pjpz/f/qaoss them. When normally incident 460-nm light is reflected from the wing, the wing appears bright when viewed at an angle of 51j8uzk/l/ ac0pqf jp40$^{\circ}\,$. How far apart are the lines?    nm

  How many lines per centimeter must a gr3(uomx+umm)b9 p9; b i*cs uocating have if there is to be no second-order s 9 usbc* uic+boupm)ox(3m9;m pectrum for any visible wavelength?   $ lines/cm$

Show that the second- and third-order spectra of white light producsratoex we/0 :,9y s/ced by a diffraction grating always overlap. Wy09atws xr,:o/ec s/e hat wavelengths overlap exactly?

  When yellow sodium light, kt0z- .thxzjm 0o /t/j$\lambda\;=\;$ 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 z8dnp wx w;w)4 (ac:er)x:axhm l55cl and the pattern is viewed on a screen 2.5 m from the graticd elx chr4)a: zxa)58 :;l5(npx wmwwng. 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 refraction of a c u. jqrqyn1iy4uiq4/ ,lear material if a minimum of 150 nm thickness of it, when laid on glass, is needed to reduce reflection to nearly zero when light of 600 nm is incident normally upon it? Do you jqiuq 1u y4n,4qyri./have a choice for an answer?

  Monochromatic light of variable wavelength is incident normally on a thin sheet . daq c,qmah3z4,hw5t of plastic film in air. The reflected light is a minimum onqhdm,z4tcahq,aw35. ly 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 aks6oc90 (:upi d*o49sh jtvexnti-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 air layer between two flat glj2l z na5d5dgs; +s+mcass surfaces if the glaad;+sn+5j zl2 cmdg5s ss is to appear dark when 640-nm light is incident normally?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the l a 6262g7qog c nn+jyr2fo6tlzight transmitted through a thin film layered on a flat piece of glass. Draw a diagram, simi 22faynog62n og7 6+jcql ztr6lar 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 is the Sun when light refle+4pf uda nunaf) f6y79b/y *z39w fzpecting off a smooth lake is polarized most strongle9b+)934ffza an/fw uy6 fpz7*yp dnuy?    $^{\circ}\,$

  At what angle should the av08n q0 dcq z:,4fhtg7h2ijczxes of two Polaroids be placed so as to reduce the intensity of the incident unpolarized light by a8:z40cctg2hif 0jn ,vdqzqh7 n additional factor (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 transmission axes arj 9i ocqu(0g)bd 7hrpm7pd/ m.e at right angles. A third polarizer is placed between the first two so that its axis )opbd/g h0r7 i7p9m.dqu (mjc 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 vert59 snji tsr.,mical, 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 s-fpw8 nat7i*sp qr *6ylit of width 1.0 cm and is pointed at the Moon, which is approximately 380,000 km from the Earth. Assume7*pw-s ni6yfrp8*qt a 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 placed at a 6jrx(dyyn* x ev(/r4e10$^{\circ}\,$ 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 :o8j b2gw3jud.ovj-a:n kqv9)w 7jdk$(n=1.34)$ 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 ,- tnahvpp b(378j+vmdzp)lq 6.0-MHz radio waves in phase with each other. They dh8n a( 3pmt+,p7 q-vpblvjz)are located 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 li 3aol9e wc7ozv,3ref7jcy4 t42 4 mfkight containing two wavelengths, 420 nm and 650 nm, enters a silicate flv cy3 jfe z9frwo4tlea7k743ci4,mo 2int glass equilateral prism (Fig. 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 wi e ynb68b zp41*a/3yi0y 2ejkgkd4krmth $R\;=\;18.4\,cm$ 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