Does Huygens’ principle apply to sound waves? To water waves?fwst :by2rqw m, 8z.0wat;+tx Explain.

What is the evidenceulvra+ 9q 8g0x that light is energy?

Why is light sometimes described as rays and sometimes as wavdrfo6lvyo1sd9 cxm-fz/w9 :/a q5 d7hes?

We can hear sounds around corners, but we cannot see around corners; y, v1cmcnxm7w8 et both sound and light are waves.c7 8 n1,mcwmxv Explain the difference.

If Young’s double-slsbncwk2vll4x8/w ezv*pzo e 8 f9l1)7it experiment were submerged in water, how would the fringe pattern be changed fz2 81ze4c7xvbo9lk l)wnw/l*vep s8?

Monochromatic red light is incident on a double slit, and the interlsqlp+ n.juh5h 1dr;: r2 )gra2y (fyrqqu :l)ference pattern is viewed on a screen some distance away. Explain how j)lnqru; 2yys r.f5 l h+pq2: q(h)dl1u:rargthe 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 infyh n shzv/8; 3r3zol8terfere if their path lengths zsyfov8 ;3nh/z3hr8l differ by how much?

Why was the observation of the double-slit interference pattern moret .4+cla- rq7)vqp2oenj . czu convincing evidence for the wave theory of lighc)4r q2..aj 7pu ql-vencto+z t than the observation of diffraction?

Compare a double-slit experiment for sound waves to that for light ,etgxqt m+ud9wda+ 4 +waves. Discuss the similaritieu4+xt+ tw,a q +9gmddes and differences.

Why doesn’t the light from the two headlights ofow/m u)u vbi7wl s33rn/vi 44f a distant car produce an interferenceu n//v)rbow73ml44ivfui3ws pattern?

Suppose white light falls on the two slits of Fig. 24–0 .+1w fnfg0rv((wlrtqzrz -i7, but one slit is covered by a red filter (700 nm) and the other by a -gr lr (+vif.0zrfw(1zwqnt0 blue filter (450 nm). Describe the pattern on the screen.

When white light passes through a flat piece of window glapceb x +(s)/kgss, it is not broken down into colors as it is by a prism. Expl/cex p)k s(bg+ain.

For both converging and diverging lenses, discu4j1mx ecwn.2lss how the focal length for red light differs from that fnmw1xjc .le24or violet light.

A ray of light is refracted through thre/q6wtn4at303h hmvz9o - (mdr;g qqdn e different materials (Fig. 24–55). Rank the materials a( h;w-d g9qma6 0ott3z vrnqh4dm/q3nccording to their index of refraction, least to greatest.

Hold one hand close to yu5r3ut8;qzrqh 6zi(r(tjxu l *ir;0 tour eye and focus on a distant light source through a narrow slit betweejt0 x r;u(3h ltqit*ri; uz(z5 r8qu6rn 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 the who4:b bzxm:tc 3nfe r7p/le apparatus is immersed in (a)ne:c tz4pbx f7 bm:/3r water, (b) a vacuum, instead of in air.

For diffraction by a single )5mopjn+s (pf slit, what is the effect of increasing (a) the slit width, an+snpp(o) j5mf d (b) the wavelength?

What is the difference in the interference patterns formed (a) by7is gfrs6;ub. two slits $^{-4}\;cm^2$ apart, (b) by a diffraction grating containing $10^4lines/cm$?

For a diffraction gravxl/;ociogz 2 .r+ cc+ting, what is the advantage of (a) many slits, (b) closely spa ox++gic. v lc;croz2/ced slits?

White light strikes (a) a diffrac yf-nh6 t*7 0 q0jnstorqa+( m)jwtge4tion grating, and (b) a prism. A rainbow appears on a wall just below the direction of the horizontal incident beam inth6ona-4ymfgj(*tr e0q )0 w7 j+snqt each case. What is the color of the top of the rainbow in each case? Explain.

For light consisting of wavelengths between hxisnz0xy) a-* sk*bt pcz+9. 400 nm and 700 nm, incident normally on a diffraction grating, for what orders (if any) would there be overlap in the observed spectrum? Does your answer depend on s.x k a-znbip0c)x 9t**z hys+the slit spacing?

Why are interference fringes noticeable only for a y k5q53yu9k upthin film like a soap bubble and not for a thick piece of glass, kky5 3uu q9py5say?

When a compact disk (CD) is m 4x gx7 me7f46pl9hwrheld at an angle in white light, the reflected light is a full spectrum (Fig. 24–56). Explain. What would you expe44ehmw6x9lf7 r 7xgpmct to see if monochromatic light was used?

Why are Newton’s rings (Fig. 24–31) closer together farther from t 93fjvdms0g6av 5wk om*ze/ omn;8p5z he center?

Some coated lenses appear greenish yellow when seen by reflected light. Whan*9yiygkp 0jrh.u7 7 et wavelengthhy k7rn*9j 7.pi0eugy s do you suppose the coating is designed to transmit completely?

A drop of oil on a pond appears bright at its edgegz(+adrf+l :vs, where its thickness is much less than the wavelengths of visible light. What can y+dvl+f z r:a(gou say about the index of refraction of the oil?

What does polarization tell us about the natur 3k1ph5zi *qwzo0u vuisj,// re of light?

Explain the advantage of polar2fk,m s osxu4vsd1e.imp 1e* *ized sunglasses over normal tinted sunglasses.

How can you tell if a pair of sunglasses is polarizing or not?/vw +wl4s0u3la/nx gr

Two polarized sheets rotatedb(6l.oq xfivre+ (,u0 1 ncpns 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 atmosph1(zw .*jjurjnu:p1 mxere?

If the Earth’s atmosphere were 50 times denser than it is, would sunlight sth)c7 l.;*b1bvf zyz8sihxjt:ill be white, or would it be 81itbbc lxj zy)h:v;*h zf.7 ssome other color?

  Monochromatic light falling on tdk9gd5iois(;2 eok +ywo slits 0.016 mm apart produces the fifth-order fkog5 9 dkeo(dy+2i ;siringe at an 8.8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 61rme )* xw36yb4gadaj0) o:qhy0 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 very narrow slits 0.04a 41aglhd** uy06r6sb tf )xxp8 mm apart. Successive fringes on a screen 5.00 m away are 6.5 cm apart near the center of the pattern. Determine the wavelength and frequency oflb*xhds u4 p0yag)r1 ft6x a6* the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of light from a He-Ne laser, with a wavelength 6ypl:n ggia9r(; 9k+uc56 nm, falls on two very narrow slits 0.060 mm apayu9gn pik +9(r;l :agcrt. 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 sl)p ps (z ng9lobxtovpekvqm3-j 3/, rmt0:b,)its and produces an interference pattern in which the fourth-order fringe is 38 mm from the central fringe on a screen 2.0 m away. What q l )0:v9r3)e 3,optmzxjm(-g s/v,pt po nbkbis the separation of the two slits?    mm

  If 720-nm and 660-nm light pavge6b;7 z) h. 3+hqim enby.issses through two slits 0.58 mm apart, how far apart are the second-order fringes for these two wavelengthmyhhbnve3sb i ;g q7z. .)6+eis on a screen 1.0 m away?    mm

  In a double-slit experiment, it is found that blue light o0-v2pco *xfr vz2zr;l f wavelength 460 nm gives a second-order maximum at a cr;c0op v 2x*vzz2fl-r ertain 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 cm apart pass m*d fxm ll3/0f 0wj.v c a)jo w.4nkt8d2b(ccnthrough two openings 5.0 cm apart in a board. At a point 2.0 m beyond the board, at what angle relative to the “straight-through” direction would there b) ml*00vxc.wm.wn k(d/ 8n 42ljdfcjaot3fc b e little or no wave action?

Suppose a thin piece of glass is placed in front oy i*o0gs 2bl,ef the lower slit in Fig. 24–7 so that the two waves enter the i2lyb,g es*o0 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 exp7st )il wc99nsb8l2 lneriment, the third-order maximum for light of wavelength 500 nm is located 12 mm from the central bright spot on a screen 1.6 m from the slits. Light of wavelength 650 nm is then projected through the same slits. How far from the central bright spot willl9i t) sl9 72bsw8cnnl the second-order maximum of this light be located?    mm

  Two narrow slits separated by 1.0 mm are illuminated by 544 nm lighj(*4e 3xblk4otv lr6 v6l 2ybst. Find the distance between adjv(6j 46krbosl *v ex2ybl43tlacent bright fringes on a screen 5.0 m from the slits.    mm

  Light of wavelength 480 nm in air falls)yxb 6g5tvs q9b4if9xkj: o*s 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) cover 7z ;l/3ytfgrfs one slit of a double-slit apparatus illuminated by 640-nm light. The center point on the screen, instead of being a;ft gy7zflr3/ maximum, is dark. What is the (minimum) thickness of the plastic?    nm

  By what percent, approximatosn;b,dx26e,s* ymo ikv, -nbely, does the speed of red light (700 nm) exceed that of violet light (400 nm) in silicate flint ;ss6biy,* ,k-mnoondxv e, 2bglass? (See Fig. 24–14.)    %

  A light beam strikes a piece of glass at a 60.7:ab sl-7 okrm00$^{\circ}\,$ 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 lc/oaa fi s x 4,dml2m-.q5xw4xight 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 wide3 a 2p,3 t y)b:lvxn:wgoy.oeytv /gq/, what is the full angular width of the central diffraction peak?e )t:.aw 32gon/lypg,y qv /ybtvx:o3    $^{\circ}\,$

  Monochromatic light f:-32l2ftr4ro hlff u palls on a slit that is $ 2.60\times10^{ -3}\;mm$ wide. If the angle between the first dark fringes on either side of the central maximum is 35.0$^{\circ}\,$ (dark fringe to dark fringe), what is the wavelength of the light used?    nm

  Light of wavelength 520 nm falls on a sliji: dmb7d dqf3 eb6g1ccxc- ezb5r.09t 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 t+3mra gt9 *m-theugd)he width of the central maximum (in cm) in the diffraction pattern )er*m9d-+a3tgu gm hton a screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nmb; vm5qt,t/ nd falls on a slit. If the angle between the first bright fringes on ei/t5 ,tv;mq dbnther side of the central maximum is 32$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central diffraction peak on a ztoe u(:p+kb .fij33t screen 2.30 m behind a 0.0348-mm-wide slit ill3toe.jbkzu (+ :3p tfiuminated by 589-nm light?    cm

  When blue light of wavelength 440 nm falls on a single slit, the first dark bandufd86jb4pvv(sd4 fy+s on 8 6 s4yu+jpfdvdf4 bv(either 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 cre (f.- jgbwmz:fates a central diffraction peak that is 9.20 cm wide on a screen tha mg-fj.(w:bz ft is 2.55 m away. How wide is the slit?    mm

  If a slit diffracts 650-nm light so thl5uyljgm8 w; :at 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 nmylu ;mjg 5l:w8?    cm

For a given wavelengt(6ybx5bl/dfsuktf 5tx*/4 65fy amw w h $\lambda$, 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 maximum when fal4 wcvth2/f0 zt,f fd(8quz:vcling on a grat,v (q:chfz0cd4zv2 u8tfwf/ ting 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 th)l2 j;pow5s4d5ibskv ird-order occurs at an 18. bspk55 lv4d;sj)2 wio0$^{\circ}\,$ 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 afcygz6ok (d,u7cm b geusr954u+ 8 od; diffraction grating is observed atgf9u4yebr6ocuk,u; 7d zc 5( +sd8gom a 15.5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction gratinsaz 0t2 oo(z.wg 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 q:g ppt 0oul ;7g ,ya hb)ynet0pk107don 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 thj3sfl:1 l eo 3(bhes.lqz-r:aat can be seen if a grating with 6000 lines per cm is illuminated with 633-n: : s3q(ole3 lej-1 zhaslfbr.m laser light? Assume normal incidence.   

  Two (and only two) full spectral orders can be seen on either sdsam)n pvgoc+i7aa043 4rpy :r d oy5,ide of the central maximum when white light is sent through a diffraction grating. What is the maximum number of lines per cm for the gr:y4 )yop adp,c0rd4r 57+nog3s iaavmating?    $ \times10^{ 3}\;lines/cm$

  White light containing wavelengths from 410 nm to 750 nm falls on a gratingl0bv09b po6fxt,ygk3 with g k ytf ob009v,6l3bpx$8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser whi06emnu h( yp0z) wvfornd;*1,l+uremch produces 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 spect8 e2hfl*7rif0 +juvxnrum 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 stron3l 8 i60hrq )nwq.iqayo*85d2u fgotd gly reflected at the center of the outer surface when illumina8 yowqa) d6.u2inf5hi q8lqt r0*o3d gted normally by white light? Assume that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the dark fringes in Examqv9sv-b6 ioy(l g7cg.t *yv 3jple 24–8 if the glass plates are each 26.5 cm long?bs l3 vqi *gytvo-9y6.cg (v7j    cm

  What is the smallest thik9-.u p(szuam;gon:39g j pbsckness 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 yellow (3 ugm0fz ;nhchmh;2/o$\lambda\;=\;570\;mm$ 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 cou 4ics6pm pzn:ki5k7n d.vt6z5nting the dark spot at the center) are observed when 550-nm light falls normally on a planoconvex lens resting zik v:5mns.6tpzi6kd745np con 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 opticall-k2 /zq 0n 3d,4e ex)efgqbeo9hp2rv oy flat glass, as in Fig. 24–33. When light of wavelength 670 nm is incident normally, 28 dark lines are observed (wi/2f, no-p3revk 9dgxb0oq )q ze2 he4eth one at each end). How thick is the foil?    $\mu m$

  How thick (minimum) should the air layer b-gihk 5yd4qh90l5jga r-a (wbb5 d0f q6fy nf8e between two flat glass surfaces if the glass is to appj h4g 5yqbf w0f dg8y-ahl6(f-q nikr55b0da9ear 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 stole.bk9o4md 04ljrelq v5n 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 alcohqba7t-ebo2bdp)qi ; j5 kf6u/ol $(n=1.36)$ 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, the w g tu6 nz82xkb)(r vnot4+6yjdiameter of the eighth dark rinytn( 2g)6rn w6t4+8vox k jubzg 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 intecsj/h:7 ) 25kxgijgbi rferometer if 644 bright fringes are counted when the movable mixcb/2j g khgj5)ii7: srror moves 0.225 mm?    nm

  A micrometer is connected to the mov u-a/q qkfedjn *lu1-q u99;ldable mirror of an interferometer. When the micrometer is tightened down on a thiq-n-9a* ulq1;l9f ujd/qkd uen 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 mirror//h0e +tq.u9 tcv ggme45poxr $M_1$ 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.(p gx07lslqbur y(t9a;k /f2;txi1jj 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 bks;q/(al ytgxjpux( 0 f7tl19 ;2 jira 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 orienoqtl)bh :5: dmted at 65$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s angle fozkmf8 vff.d3z191 opxr an air–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for y9c7yfpa;e. a(w zs+aa diamond submerged in water if the light is hitting the dia7awsp;ef y9.+zycaa( mond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the light passing x*s:tk9k( nblw 9x2xw through them is a maximum. At what angle should one of them be placed so that the intensity is subsequebwswxxt 9kx 2n( kl*9:ntly reduced by half?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as to reduce the .y3b 8b+f1h koo 6oemkintensity ofokef8 1.ohm o k+yb63b the incident unpolarized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are orien-nrouv0hf r** ted 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 3m:q a*9brm kk)8.0$^{\circ}\,$ 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 refleck xve;5 c zet/crf)+a6tions off the surface of water for light coming from beneath the sux fk c6ea);r5vztec+/ rface? Compare to the angle for total internal reflection, and to Brewster’s angle from above the surface.
If the light is coming from water to air, $\theta_{p}$    $^{\circ}\,$For the refraction at the critical angle from water to air $\theta_c$   $^{\circ}$ If the light is coming from air to water $\theta_p'$   $^{\circ}$

  Unpolarized light pa,+w78+ yef g* kezuwhrsses through five successive Polaroid sheets, each of whose axi*7,+z+ug8kewye whrfs makes a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength 5wbd z ii(drcl:rs,t :hk2i/8$ 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 8e *)fa7 rzvm 9 ayka3u)ykpzel(t;+y airplanes can interfere with the direct uv+e*r7mz8e a9tkk)pfz);a (ly y3 ay signal from the station.
(a) What kind of interference will occur when 75-MHz television signals arrive at a receiver directly from a distant station, and are reflected from a nearby airplane 118 m directly above the receiver? Assume $\frac{1}{2}\;\lambda$ change in phase of the signal upon reflection.  ----待选择----constructivedestructive 
(b) What kind of interference will occur if the plane is 22 m closer to the receiver?  ----待选择----constructivedestructive 

  Red light from three seu+ ix4:*nt:dzskg. k zparate sources passes through a diffraction grating with u4:gi:*x. d +kznkzst$ 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 throhu:hc* vx o/)qugh two narrow slits 0.60 mm apart. The screen is 1.70 m away. A second source of unknown wavelength produces its second-order fringe 1.33 mm closer to the central maximum than the 590-nm light. What hxu)q:v*och/ is the wavelength of the unknown light? $\lambda_2$    nm

A radio station operating at 102.1 MHz broadcasts from two identicad ny5. +n(4onxkeo5/f7rgvnul antennae at the same elevation but ovnn/e4xg7k+ dof(nrn5.5u y separated by an 8.0-m horizontal distance d, Fig. 24–60. A maximum signal is found along the midline, perpendicular to d at its midpoint and extending horizontally in both 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 outside9 zs0jk;0s.ujs-y +ejge7i qk doorway 0.88 m wide, and blows a whistle of frequency 750 Hz. Ignoring reflections, estimate at what angle(s) it is not possible to hear the whistle clearly on the playground outside the do-s igjj sq9k ezyesk+ .u00;7jorway.    $^{\circ}\,$ either side of the normal.

If parallel light falls on a single slit of widnu1 jfv;,ye0 pcilz4 ue9t)j) th D at a 30$^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain:k)u r5dyn aq z4 ohkh;z3s w/:pq-z1a beetle have a series of parallel lines across them. When normally incident 460-nm light is qhqyzh/5) 1wa:psuza3- n4okr :zd;kreflected from the wing, the wing appears bright when viewed at an angle of 51$^{\circ}\,$. How far apart are the lines?    nm

  How many lines per centimeter must a gratr:e zdz9vco8/ing have if there is to be no second-order spectrum for any visi z9/:o8zevd crble wavelength?   $ lines/cm$

Show that the second- and third-order spectra of white l,nxb,h8yhw/yiwx6n+)gk s lf .hr7 s+ight produced by a diffraction grating always overlap. What wavelengths o .6/rwxxlis8f g+bnnhs7,w ,y +hyhk)verlap exactly?

  When yellow sodium lighh .qm z33 kdrzpft1/i*t, $\lambda\;=\;$ 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 witoyz xz 1) erw.;n6lsg)h and the pattern is viewed on a screen 2.5 m from the gr1yz6 n.e slgw) zo;rx)ating. 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 of bly*)n+7eqlz 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 n7blz+y*l) eqit? Do you have a choice for an answer?

  Monochromatic light of variable wavelength is ii-on.7va qd -x7c n/auncident normally on a thin sheet of plastic film in air. The reflected light is a mi o7n7qxd.-ic/na-avu nimum 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 coatinpi/js ;ydty;mm 2m:fa )r q*/xpcwb;- g $(n=1.38)$ 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 (n 0vsh;f,eg)gca/o q5* q4 zvanon-zero) thickness for the air layer between two flat glass surfa*zh, /afqn5av vc)ogeq; 40s gces if the 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 transmitw6 /70 djpemoated 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 7d0 woj6 /epmarequired 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 reflecting sidfa3l) -9i1qu yx. 7oy xda8i gs:5boff a smooth lake is pf)b8u- 3gsd9.1i si dx aoy:xilqy57 aolarized most strongly?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as to )s f nj .,p/ ty.8snu*ttwiau/reduce the intensity of the incident unpo/w.fy/ i)*ua,n un spt.tjts8 larized light by an additional factor (after the first Polaroid cuts it in half) of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light fall3c2 uq rzsa+tw. d k(dr2 hci0v/26kgjs on two polarizer sheets whose transmission axes are at right anr.wrck +632sdc/athi 2ku (0j zqg2d vgles. 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 u.q k-8wj* *r/4ylnr*ku mdxd0w*ogm 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 through a slit of width 1.0 cm and is pointed at thev6d63t* s:aourv kc:a j8bku3 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). Estik u*j33ao8 t r6dvub:6ca:skv mate the width of the beam when it reaches the Moon.    km

  A series of polarizers are eo6ho 52;v dda7k sndeh)xv 6l(ach placed at a 10$^{\circ}\,$ interval from the previous polarizer. Unpolarized light is incident on this series of polarizers. How many polarizers does the light have to go through before it is $\frac{1}{4}$ of its original intensity?   

  A thin film of soap -sfn* xo*ldjl;h, y *g$(n=1.34)$ 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 in phase1/3vvk88 mrdviybg)ysrq1 inq6 pphz: e o +6, with each other. They are located at poiysqry3gvev p, 1qd8ki:)6 o 8 b ni+6h/z1rmvpnts $S_1$ 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 twocm3je3u4m5; c meobj- wavelengths, 420 nm and 650 nm, enters a silicate flint glass equilateral prism (Fig. 2-ce bmmjco 335ujem4 ;4–58).
(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 ldd3 g*k,pw d q ,epe z8vyfel2q*5s9+lens has one flat 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