Does Huygens’ principle apply to sound waves? To+yr0d ms: ;rzn water waves? Explain.

What is the evidence that yqz;0ci :r+.k5t tkmc light is energy?

Why is light sometimes described awug zr a;49)cbs rays and sometimes as waves?

We can hear sounds around zj an;3i6,rq nz6s2f7armg -fcorners, but we cannot see around corners; yet both sound and light are waves. Explain the frz23jm -r6sqiaag 6z fn ;,n7difference.

If Young’s double-slit experiment were submerged in water, how would th, rb gwhxd51b qg2*(gpe fringe pg(bb5 qh*2w,r dgpgx1attern be changed?

Monochromatic red light is incident on a double slit, and the interference patyzl +z/*ixlb di1:2 tttern is viewed on a screen some distance away. Explain how +xtdbii: t21 z/ly*zl 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 destructi*aqbod ggim f p*1.j+/vely interfere if their path lengths differ by how mucfbj1a* mg+d/pq iog*.h?

Why was the observation of the doublm+ p+rsz ,,tgee-slit interference pattern more convincing er, ,spmzge t++vidence for the wave theory of light than the observation of diffraction?

Compare a double-slit experiment for sound waves to that for ml9y,t .l,fp blight waves. Discuss the sifb,ly9 l,mp. tmilarities and differences.

Why doesn’t the light from the two headlights of a distant car p4p8v+..ca bx ub*a/eaw ycr ;1i,vjykj+p. zmroduce an interference pat.8b1 .+4 ea; xiv wma*pbj prayccuk,y/.zjv+tern?

Suppose white light falls on the twoo;pg(g;/ oqho9wd zhn 1 9dby9 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;ygn9hb 1/d qgwphz9od9(oo; the screen.

When white light passes through a flat pics,4g pro mg2z;q9*axece of window glass, it is not broken down into colors x4r2ms cp9g, *zoga ;qas it is by a prism. Explain.

For both converging and diverging lenses, dz jbg1 6vq0q oq7q 4:)f0pfyliiscuss how the focal length for red light differs from that for violet l p06bq )i401qqo flyjqv7zg :fight.

A ray of light is refracted through three differen)hv*lg1 qong*5u/ jmm19tzsw t materials (Fig. 24–55). Rank the materials according tjhs*qz19w15tl u v) g* no/mgmo their index of refraction, least to greatest.

Hold one hand close to your eye and focus on a div,nb/h ecp*hvw f5s** heyck*mb4/ ;u6s zb7ustant light source through a narrow slit between two fingers. (Adjust your fingers to obtain t*,epz*4hb7 e6 kc/;bs *5hsvufyhc/nwmvu*bhe best pattern.) Describe the pattern that you see.

What happens to the diffraction pattern of a single slit if the w+f.ld +ysw/ovnt4 1slhole apparatus is immersed in (a) watldw1sofy+ +ln/t .sv4er, (b) a vacuum, instead of in air.

For diffraction by a single slit,s.w, hgeya8.+ ;ngayl what is the effect of increasing (a) the slit width, and (b) the wavelength?+hylws.y8 ea n, ;g.ga

What is the difference in the interference patterns formed yr4k2qn8i/y h (a) by two slits $^{-4}\;cm^2$ apart, (b) by a diffraction grating containing $10^4lines/cm$?

For a diffraction gratin:r3u dvu2pj 3wyr7*7bfkkkh 2g, what is the advantage of (a) many slits, (b) closely spacedk7yjr2v ufku7r k2hb:pd3 3w * slits?

White light strikes (a) a diffra8 9rt l1z5slfdction grating, and (b) a prism. A rainbow appears on a wall just below the direction of the horizontal incident beam in each case. What is the color of rd 59flt1l8szthe top of the rainbow in each case? Explain.

For light consisting of wavelengths between 400 nm and 700 nm, )7/ 4ap rdyre.isb7 whincident normally on a diffraction grating, for what orders (if any) would there be overlap in the observed spectrum? Does your answ7.y47berrwd hpsa/i )er depend on the slit spacing?

Why are interference friu*r 3s28:zf1 +-c ;xucb nhdaeegf4 nxnges noticeable only for a thin film like a soap bubble and x+-e u sbnru2n;ga e8f:df1*3 hx4ccznot for a thick piece of glass, say?

When a compact disk (CD) is held at an angle in white light oiaka7 u)l(5p, the reflected light is a full spectrum (Fig. p u il)o7(aka524–56). Explain. What would you expect to see if monochromatic light was used?

Why are Newton’s rings (Fig. 24–31) closer together farther from the centerwn. 2lek6kbp+?

Some coated lenses appea vw4m*mvty8m )qq,k21 6rnaf jr greenish yellow when seen by reflected light. What wavelengths do you 1 n6mvaqwqr) k,8j4yfm *vm2t suppose the coating is designed to transmit completely?

A drop of oil on a pond appears bright at its edges,j qse 7:u((9lobg6 ccbbn3l*c where its thickness is much less than the wavelengths of visible light. What can you say about the index of refraction ocl b(g6csbej:l7*39c oq nbu(f the oil?

What does polarization tell us aboub n9m/ pl-aox-t the nature of light?

Explain the advantage of polarized sunglasses xj95b, aawvj+2fz95yyytd+ m over normal tinted sunglasses.

How can you tell if a pair of sucroi s6k0t,4uz. iic )nglasses is polarizing or not?

Two polarized sheets*x5i 92oe (8hfkqiker rotated 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 Earth had no atmosphaf.2cc gqn; a:ere?

If the Earth’s atmosphere were 50 times denser than it is, would sunlight still kl f,javisd*3 n 7cn82ik 0fn-be white, or would it be some other col8,fv kfn iid*jnl-2s7cna k3 0or?

  Monochromatic light fm1 aoc1gmd3)dhzdi:mx5 2 yc2 alling on two slits 0.016 mm apart produces the fifth-order fringe z 135xdyh2c):o mmdcdm2a1 igat 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 observ: lg2d/q nxa,xed 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 very narrowpc 9ao;. sap7;mgoow5//dv ko slits 0.048 mm apart. Successive fringes ono sm7w oc/p;oa/dvo kg;9.ap5 a screen 5.00 m away are 6.5 cm apart near the center of the pattern. Determine the wavelength and frequency of the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of light fp8m u3zl n(1cib8.fq n-rjp.w 4l zn*rrom a He-Ne laser, with a wavelength 656 nm, falls on two very na(qf.i p u8n rlbw48l3-.rzz n*1mnjcp rrow 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 producexjcj)j3 n0a) es an interference pattern in which the fourth-order fringe is 38 mm from the central fringe on a screen 2.0e0jnajjc x ))3 m away. What is the separation of the two slits?    mm

  If 720-nm and 660-nm light pas7g7y7jv:av4nmxot6z ses through two slits 0.58 mm apart, how far apart are the second-order fo g7:4 azvym7nt7 6xjvringes for these two wavelengths on a screen 1.0 m away?    mm

  In a double-slit expz n;pybl3co4j0(.ppmxs3h:-r0 n zsmeriment, it is found that blue light of wavelength 460 nm gives a second-order3 04-o zpn:;0mbphplnj.3sxr( m czsy maximum at a certain location on the screen. What wavelength of visible light would have a minimum at the same location?    nm

Water waves having parallel crests 2.5 ca/ s;uafinr t y;e.0 nety/ ;(g7q4okkm apart pass through two openings 5.0 cm apart in a board. At a point 2.0 m beyond the board, (tk/y eok; n/;0uae .ig7fysar n; tq4at 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 lr6e,;* 0bxhdqu( sox dower slit in Fig. 24–7 so that the t sxdo*bqe h,(rd0x;u6 wo 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 light of wavelen6csv ; *bghc)qgth 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;g *qh6)vcc sb 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 k ximcovaz ihfxx ,jk0 -)b.6,*x22zc1.0 mm are illuminated by 544 nm light. Find the distance between adjacent bright frinxi0kc.xz2v bm ,x2cf- izk)*oh ax6, jges on a screen 5.0 m from the slits.    mm

  Light of wavelength 480xk2 (mtot av)( nm in air falls 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 plalp, 3c6yk/eo estic (n=1.60) 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 of t36oe,e cypk/l he plastic?    nm

  By what percent, approximately, does the speed of ,w witdg-k7 e+red light (700 nm) exceed that of violet li+,w dw-7i kgteght (400 nm) in silicate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece of glass 8+teenp e u7tfk2x1y6at 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 ligqvu i dqs3p3 bd-f0titja)p18q :gq.5ht containing 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 the fs-rr4b p uef):ull angular width of the central diffraction prr pe f)u-:4sbeak?    $^{\circ}\,$

  Monochromatic light falls x2a01.2 .qg hvlt7 bj*yqmipyon 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 1 lcgst( /oj8lmlvd(5-lr9 mt 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 is the width ofoi /rxv j 2a j.xrcwdl*z:.68p the central maximum (in cm) in the xj*r 2.oc :6jdx/vz8aplr i.w diffraction pattern on a screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm falls on a slit. Ifkd(zr,1 yu3k(f wnc+khv /)cj the angle between the first bright fringes on either side of the ce1ckj(y + nkz3ufwrh kd,)/v(cntral maximum is 32$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central diffraction peak on a screearc7qbp;aoz(nt n w7b +n)8f +n 2.30 m behind a 0.0348-mm-wide slit illuminated by 589-nmft 8nr+n7z7 npa(a+w;q )b boc light?    cm

  When blue light of wavelength 440 nm falls on a single slit, the first darlz1rr x4v e6v 7nt;j5wk bands on eitherrx zl;14 tr7jv5we nv6 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 )o,0(4m fqj d m+;uiizo, lrgna central diffraction peak that is 9.20 cm wide on a screen that is 2.u fl)+n,; ,iq4rm zg0ojim(o d55 m away. How wide is the slit?    mm

  If a slit diffracts 650:ndg)3y gt b)o-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 maxiyntg 3)ogd):bmum for light of wavelength 420 nm?    cm

For a given wavelength odsh,jme-3vx8v n ; ;qgt*/ij$\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm light producey3heqli0z*gv:)k k /x a second-order maximum when falling on a grating whose sllex*iv :0/gzhk kyq3) its 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 third1onl9fih9 vl py 7vfl+/jp )j3-order occurs at an vjf 9 lnfo3p9li7v/ 1)hlp+ yj18.0$^{\circ}\,$ 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 grauvgi:tw6: i 5oting is observeiio 5t: 6guv:wd at a 15.5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction gratingu47/xt08z vqkengl*3vm gzqe5 a s6k/ a r-m,a 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 normal6ah rv i*,1if8 hd;. sfec1dgily 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 order that can be seen if a grating xczuiouu z8r lp-r+n ,-jfn;rg 4 )0p3with 6000 lines per cm is illuminated with 633-nm laser light? Asfg;,opnrjnu zrc uix8zru+l-0 4 )-p3 sume normal incidence.   

  Two (and only two) full spectral orders can be seen on either side )jty(/g / ggcad 6qmg7of the central maximum when white light is sent through a diffraction grating. What is the maximum nu7y/ )cgqmj6 a(gdg t/gmber of lines per cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containing wavelengths from 410 nm to 750 nm falls 0ik,-h +w.-ous+ut saehozb, on a grating with,h uoizk0shwea- ubt-. ,++os $8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which producx o0q ,,q0 zs-:m4ijfjgv pgu1es 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 likactvl npdttitvc;j ; 3w718l,;w:h8s1 mxs5nes 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 l61 q u7kiydfyogu1cv.r 33y.120 nm thick, what wavelength is most strongly reflected at the center of t13uy ..ukf 3l idy7rvo1gcy q6he 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 plv d2s-2xvtz )ov+io6uates are each 26.5 cm long?oxv)2zv6dt sv +-uio 2    cm

  What is the smallest thickjdgaf nac) -6 o;3fhy)tq)l i4ness 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 greenish yello(zu.hmc / nux(y,*cgv w ($\lambda\;=\;570\;mm$ 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 315rt. tuhe hg..eb y+*n;+wi gw dark Newton’s rings (not counting the dark spot at the center) are observed when 550-nm light falls normally on a heyh . .*5iu+g;nrwtgbw.te+ 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 end of two pieces of optically flat glass, as inlqx*zdxs72avto9 lxh:;oj9 m 6/yf9esg c l43 Fig. 24–33. Whenfhcso* ; 49x dx2t x j7gov3yl m9lsz:le9/6aq light of wavelength 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 betwe8 ft(*v m6amxden two flat glass surfaces if the glass is to appear bright when 450-nm light is incident normally? mt(*d8fxa6 v m   nm
What if the glass is to appear dark?    nm

  vA piece of material, suspected of beinbcfqjqs wdt:cp6e1 ( nl+ uk3:m95n+jg 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 alcoholtz 71vmoh3x8g,kro3r $(n=1.36)$ 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 i 1fw4j;g .d5pgbiyp5 liquid, the diameter of the eighth dark ring decreases from 2.92 cm to 2.48 cm. What is the refry51jg 54wpf iigdb.;pactive index of the liquid?   

  What is the wavelength of the light entering an interferometer if 644 bright lje dcm.inolom:xh;f8 r 0b;+21s 4rx fringes are counted when th1xom;e: xn lihcfr;rm.j42+o8dl 0 sbe movable mirror moves 0.225 mm?    nm

  A micrometer is connected to the mov6-kigvb 8v; z31zt3apms,bgkable 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 thickn-vk13zs 8;m ,pbgktgz6 v3biaess of the foil? The wavelength of light used is 589 nm.    $\mu m$

  How far must the mirror h9ixce zz5 +;wdqro0p( p,*rw$M_1$ 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 interfero5h 8si / jvlkwhckt92x334lmsmeter (Fig. 24–59) passes through a small glass container containing a cavity 1.30 cm deep. When a gas is allowekh348v tlkx/ j 3sm2 i9sw5hcld 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 interferometer is in vacuum. $n_{gas}$

  

  Two polarizers are orhomstdf) b e.;p:ukx et .33 7l8o7piiiented at 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 a.v:is6 diw is5ir–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle fortir 0 wp,(bk:q a diamond submerged in water if the light is hitting t :b0qp ,(riwkthe 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 maximum. )o ;,ie r;+imwsv,hzmAt what angle should one of them be placed so that the intensity is subsequently reduced by ha ,ihz+)movmsr, ;ie;w lf?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be2x u bp9h si dhv+gbhr1/n0,v0 placed so as to reduce the intensity of th2 0vp+ hvxs,nir0bbg1d hu/ h9e incident unpolarized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are oriented at-elp 6.6):o wz- wz0jgodw1ypt9d yxx 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 fx2oqj +zh*1 yat 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 *o(k l8pulf7(uv.gwdfor 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 angle from above the surf ulud vg (po*k.8(7lwface.
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 successi(hf 5ubqik36 mve Polaroid sheets, each of whose iq3kbh(u m65f axis makes a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength 9 (g:, y f wom o8av.n,jcfqa(yjybh7o;gk0o,$ 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 gn0/ci1x7ef we,ua7aes reflecting from mountains or airplanes can interfere with the direct signal from the stagnf u7/70 xe ,iaa1wection.
(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 sourj8lf.ly+vh *1*ii k ngces passes through a diffraction grating with khnlf8ij1*+*yl ig.v $ 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 slits 0.60 mm apart. Th( 73s/36sza pdujqgnv e 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 /d6sqp jazvn33s(ug7 than the 590-nm light. What is the wavelength of the unknown light? $\lambda_2$    nm

A radio station operating at 102.1 MHz broadcastse mbv(i+e4/xf 3i5 ppy 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, perpendicmp bepy5/(i4+f 3ei vxular to d at its midpoint and 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 b3,7ntp(p3 mu g1mxl ;1wjbljslows a whistle of frequency 750 Hz. Ignoring reflections, estimate at w b ,3(pspj;1wtgx17jl3ulmnm hat 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 o*)1 tmk7kosln f width D at a 30$^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain beetle have a series of parallel lines across them-c6 sfu/w e6q/kbuy3 /c-b a8,xjvreq . When normally incident 460-nm light is reflected from the wing, the wing appears bright when viewede3/ucj-c buxak8svry,q6eb6/q/ f -w at an angle of 51$^{\circ}\,$. How far apart are the lines?    nm

  How many lines per centimeter must a grating have if there is to be 1 mzub3jd*lfiop2 1;z q+a 2sfno second-order spectrum q +u 1zm*jb 12o2fz3;fdialspfor any visible wavelength?   $ lines/cm$

Show that the second- and thwlxm e)n)y :m+u2xm 5nird-order spectra of white light produced by a diffraction grating always oxn +)uw2)nx lmm:5 myeverlap. What wavelengths overlap exactly?

  When yellow sodium light xl)xcyvacut7ds ;0,lnq k 928, $\lambda\;=\;$ 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 patter9 6 lbudews7:3xmi5 hnn is viewed on a screen 2.lix 6e3:d7u9m nbs5wh 5 m from 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 refraction of a clear material if a minimum l6mrjb+; ul o.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 nr;ol.mb+ lj6 uormally upon it? Do you have a choice for an answer?

  Monochromatic light of variable wavelength is incident normawcq7 a bjrei*;2 .3wgtlly on a thin sheet of plastic film in 3 w*tj cgrw7a2qi. ;beair. 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 ag3 ;9*nruf b*4ml apbthickness needed 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-zero) thickness for the air layer between two flat t. e ;+od+cnups/+qv gglass surfaces if tht ++.vqn+;d u/ocgsep e glass 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 light tr-, b(xy uml)ya 6ohs/iu.w7 bpansmitted 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 for maxima and minima. Consider all possible values of index of refraction. Discuss the relative size of the minima compared to the maxiw6ulx hbi bm(y7-,o)ays /pu.ma and to zero.
24-30
24-36

  At what angle above the horizon is the Sun when light reflecti axgon7bf1iur/z+ehfl 6-+;d ng off a smooth lake is polarized most strxbrl u +/zfhd -oeia+76f;g 1nongly?    $^{\circ}\,$

  At what angle should the axes of two Polaroids bz8 mayi wc: 2l:gio4*xe placed so as to reduce the intensity of the incident unpolarized light by an additional factor (after the first o4lx*miz2aw 8 c:yg:iPolaroid cuts it in half) of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light falls on two polarizer sheer jec+w-l8tib3 * m4w9 bzkd6lts whose transmission axes are at right ang6w+i-w cjrd zle*bk9t8 mlb4 3les. 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 vert)(, muc:cevv sical, 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/,ufpvc6 ;8kvn yq,hntv y:/n lit 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 reachesnqvvv ypy:nt ,/ ; unf/c8hk6, the Moon.    km

  A series of polarizers are each placed at a t r)uokpq0knoa 19)p+ +cx:ht ,tyable9g.;g10$^{\circ}\,$ 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 l5ui -l/qktr-m;t*by$(n=1.34)$ 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 w4 x+ 1qu*9a r0phyuh kpm9/nndaves in phase with each other. They are lo1hp9rny d* /x k04uuah +pqm9ncated 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 wavelengths, 420 3 s, em(ty/se;nkju9u nm and 650 nm, enters a silicate flintke;y9us3mu e n,(js t/ 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 andmilz e7z6l.(ctv*y)2e v une3 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