Does Huygens’ principle apply to sound waves? To water waves? Explainwe1r(g *ex c2 :qyye1+dn4igpjyh , ;c.

What is the evidence that light is energy?z3 hjma45,bfj3,tzt ;ki;xz w

Why is light sometimezt8b;thib2u f, .p4 8t okeku4s described as rays and sometimes as waves?

We can hear sounds around corners, but we cannot see around corners; yetg+r tnz khjkmx /84k7i ;tsb8v x/+sr) both sound and light are waves. Explain the differenc+jkvmrz;4 t rss7 kh+x8gb/k 8in )t/xe.

If Young’s double-slit experiment were submergwg9s yb+fgt3.2i*( as xacw*c ed in water, how would the fringe pattern 92f*by( sca*cis.at x3+wwg gbe changed?

Monochromatic red light isbw:xpfsh;5*.s i* xb0snm tp4 incident 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 lp0 bh*5ws4mx: ;b.insfxt s p*ight source is replaced by a blue light source.

Two rays of light from the same source)h4 f0 k8wlvkm g5xu(opj0f lx1ub m. 3(y8egb destructively interfere if their path lengths differ by how muchu8l yk4ol3g gmb 8wxehf0 ()(umb01kf5jx.v p?

Why was the observation of the double-slit interference p7nu,amxorx48hch:k; /l.u hpattern more convincing evidence for the,7/p;a mnxohuh4h k xluc:r8. wave theory of light than the observation of diffraction?

Compare a double-slit experiment for sound wavrl36o:ko)uz6 7n zckc es to that for light waves. Discuss the similarit:oznlz66k c7rck3u )oies and differences.

Why doesn’t the light from the two headlights of a distantw4+itg+zcef+ car produce an interfeftze +c +4+igwrence pattern?

Suppose white light fa ::lzhoobk4h/.ac0zdv h0/ ivlls on the two slits of Fig. 24–7, but one slit is covered by a red filter (700 nm) and thh0io hav::/zvz /4bd0l. k cohe other by a blue filter (450 nm). Describe the pattern on the screen.

When white light passes through a flat piece of window glass, it is not brod 8+tb.f* o0gaz1sbgx*dp9e lken down into colors as it is by a pris+.e9 d blgta8 1d*g*sf0pbxo zm. Explain.

For both converging and divnf hc(8 zt5vw*u9 7 wscnn. r7fa7k9iaerging lenses, discuss how the focal length for red ligh nn 78rtz fs*c7u(vkin79ha9w wa.fc5t differs from that for violet light.

A ray of light is refracted through three different material cwc/w-ot9ep; s (Fig. 24–55). Rank the; ow/ pw9tc-ce materials according to their index of refraction, least to greatest.

Hold one hand close to your eye and focus on a distanv 5j nkrb zy/:q we(/,ig9bz7yt light source through a narrow slit between two finger /y(ngqb: z97i5v ,k wz/jybres. (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 whole aa z9+lv 45nvzf;a,nyd/g1,haaqv5wepparatus is immeae1l4av,hyaqzg/ +v dnw ;595a,znfv rsed in (a) water, (b) a vacuum, instead of in air.

For diffraction by a single slit, what is the effect of increasing (a) the slit*2mqdb19+au skc cm+t width, and*d1+ca 2mq+m tb9uk cs (b) the wavelength?

What is the difference in the interference eswmi q e *zxxaeq5b9- yz7:eu64v+yw nh**,u patterns formed (a) by two slits $^{-4}\;cm^2$ apart, (b) by a diffraction grating containing $10^4lines/cm$?

For a diffraction grating,vlf 0x0bwasia+ (mpq:wn.4p 4 what is the advantage of (a) many slits, (b) closely spaced sla. xwm0v0+q n(4: p4pfbliawsits?

White light strikes (a) a diffraction grating, and (b) a prism. A rainbow app h 3xg p)5nkd:/viqc0cears on a wall just below the direction of the horizontal incident beam in each ckciqnp dv h:503xg c)/ase. 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, incid 5aequjw 66t1gent normally on a diffraction grating, for what orders (if any) would there bu 166ag 5eqjwte overlap in the observed spectrum? Does your answer depend on the slit spacing?

Why are interference fringes noticeable only for a thin.3x4.r qgj ovbb q;dcdd3o0)i film like a soap bubble and not for a t3ddg; jq. )bvib43xr0.do coqhick piece of glass, say?

When a compact disk (CD) fg(mb hw:4q .kbujm3 5zrb;,bis held at an angle in white light, the reflected light is a full spectrum (Fig. 24–56). Explain. Whatugb5 bbm,fm r.qbwz4:(hk3; j would you expect to see if monochromatic light was used?

Why are Newton’s rings (Fig. 24–31) closer togetheumykv-.vf.p 641xonw x llb,0g;hg( ur farther from the center?

Some coated lenses appear greenish yellow when seen by reflected light.l iv(vbdi7 2c/un 96xy10kpwr What wavelengths do l1dcvi(6n02/ ixru bv79 wkpy you suppose the coating is designed to transmit completely?

A drop of oil on a pond appears bright at its edges, where its 4+nn 9km 1ex*nzgt 4omk/a)aythickness is much less than the wavelengths of visible light. What can you say about the index ofyanaok 4+t/)n n zm9*gex1m4 k refraction of the oil?

What does polarization tell us bqe)y nxa/c 7.about the nature of light?

Explain the advantage of polarized sunglasses over normal tinted wu2ng, s+4k/dv:o );n ttjo g3-ctsba sunglasses.

How can you tell if a mq3:ji l ;, v;m8uoesc( eoc/spair of sunglasses is polarizing or not?

Two polarized sheets rixk34u0bt9q ootated 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 s1yh oc2j-w(eq ky if the Earth had no atmosphere?

If the Earth’s atmosphere were 50 times denser than it is, would sunlight stie r 8tg33g(m0uu .png)ikbb/ pll be white, or would it be some o)pkm(bb.i upegtgu8 /n0rg33 ther color?

  Monochromatic light falling on two slits 0.016 mm apart produces theuawht 22 5lewkwkaq+wb22 8 /e fifth-order fringe at an 85/e+kql a uwwea k2w2 22tb8wh.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 5lo+cj,y: f aeu p6 j;(;lkvdez3nv1rangle 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. Succes xkpci0dyt0jv 9pp64(sive fringes on a screen 5.00 m away are 6.5 cm apart near the center of the pattern. Determine the wavelength and96j0k dpt cvi0px (yp4 frequency of the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of light from a He-Ne laser, with a wavelength 656 nm rw2: mv,4l9wx bviz) ;olt2zs, falls on two very narrow slits 0.060 mm x,ts2:v) l rwlzw9z ibov4;2mapart. 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 fos/nhw4a;d v6jkn*/ salls on two slits and produces an interference pattern in which the fourth-order fringe*ovn h/as/d4 k;wj6ns is 38 mm from the central fringe on a screen 2.0 m away. What is the separation of the two slits?    mm

  If 720-nm and 660-nm light passes through two slits 0.58 mm apa//z/jf l umwq2rt, how far apart are the second-order fringes q/uwjm fz l//2for these two wavelengths on a screen 1.0 m away?    mm

  In a double-slit experiment, it is found thkxlw3bq5en ju.qou)*s5 y b*6at blue light of wavelength 460 nm gives a second-order maximum at a certain locationq5q*w 5yno3b.u)e6kuj lb* s x 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 through two opengu:twbn+lq rv tj)-7/ il:ib6ings 5.0 cm apart in a board. At a point 2.0 m beyond the board, att: itbu6r:in)gqjbl-/ +lw 7v 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 frontsg04 jzu2f/e u.j. 5itg (5rvbha (xpd of the lower slit in Fig. 24–7 so that the two waves (t vg 4j(gdp.e5/.uuasr5 20 bhzxjfi 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 wavelvjqnvq,z - k0+ength 500 nm is located 12 mm from the central nvqk zv0,-qj+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 will the second-order maximum of this light be located?    mm

  Two narrow slits separated by 1.0 mm are illuminated by 544 nm ligtfnh: wb */r6iht. Find the distance between adjacent bright fringes on a screen 5.0 m from the slits. hrb/*: iftnw 6    mm

  Light of wavelength 480 nm in air falls on two sl4g(b3v5eqj2ml ss 4++ 8yjiabtx2l iuits $6.00 \times10^{-2 }\;mm$ 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 appa(xo(h nt2mb3s3qc; s- iram h1ratus illuminated by 640-nm light. The center point on the screen, insteads q- t( 2(xi1noms33r cha;hmb 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 nm) exceed t; yl-y;i chtv 2:mqmb/f 5 mux8kj)j.zhat of vvlmiyzu: jh.tm)m5 by;ckjx -;/q 2f8iolet light (400 nm) in silicate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece of glass ;34ki(y3 h;yuc sahsz 9,-s+ jydnulhat 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 e uc49-lysk o4two 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 0.07- ocq)cf-k ephpaf5. 440 mm wide, what is the full angular width of the central 5f-cq-a he7p)pkfo.c diffraction peak?    $^{\circ}\,$

  Monochromatic light fall jj9a m(hksn4ck1b0* ys 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 odxzu*7xt 0e, bn 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 w6vby2s1al h6 the width of the central maximum (in cm) in the diffractiw1a2 hb6vsl6y on pattern on a screen 5.0 m away?    cm

  Monochromatic light of wavelengt7bc kvuyebxz),j 5 mnw*vj(: -h 653 nm falls on a slit. If the angle between the first bright fringes on eithez5)yn: 7 bkec (,jux vvwm*j-br side of the central maximum is 32$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central diffraction peak on a screen 2.30 m behind a 0.034nv1l9wa;z z7 i8-mm-wide slit illuminated by 589-nm lign ;iz71lwa9vzht?    cm

  When blue light of wavelengxhw4l we7vni4 /18n qyu1e:vb th 440 nm falls on a single slit, the first dark bands on eb l84 vqxe1uy w:h4wni e1/nv7ither 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 f,fedz i :6*lo*lgv g+jalls on a single slit, it creates a central diffraction peak that is 9.20 cm widzlofj ,d *g:6+* vielge on a screen that is 2.55 m away. How wide is the slit?    mm

  If a slit diffracts 650-nm light so that the difr4 u 3;0vbaupnfbc+t( fraction maximum is 4.0 cm wide or0pb na;ufb4(vt c3u+n a screen 1.50 m away, what will be the width of the diffraction maximum for light of wavelength 420 nm?    cm

For a given wavelengthnz en0nk: )u7jj//y,q tb5qb2 u kt7kf $\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm lightd)xc pdvpj r2nr(w3m 9 70rpd( produce a second-order maximum when falling on a grating whose slivdppj 97r(0dp3 2 xwc(r)mr ndts 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 haq/ox . 9qzmsj+h,a,z 0cm: swhve if the third-order occurs at azmc,j9h+ /am x: q0zsoq,.swh n 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 light falling on axxun1-9imun e,4 eq5l diffraction grating is observed 4-u5,ei x x l1meq9unnat 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 1.bg )1uun b zc(9/76t;lzjy:* bgtrrznhwgx 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 on arwp 0nrrni10o31+g4jf ;zkpie/jf d 1 pk0 o(h $9700-line/cm$ 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 orgp(b m6yt+1pzder that can be seen if a grating with 6000 lines per cm is ip+6 btp1gy (zmlluminated with 633-nm laser light? Assume normal incidence.   

  Two (and only two) full specz3wwkf*g2g1 2 uwjad6 tral orders can be seen on either side of the central maximum when white light is sent through a diffraction grating. Whakwguw z21a6jd *2wf3g t 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 falls on a grating wi (9 *p*+ufogbzmj; g4:e2 pc(ygbwernthb2y*pu*g; 9woze+p( rgbn:ejf c(gm4 $8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which produces monochrg6e kyyg 9x-o/omatic 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 o duzpjv :j(at(+ ns:2a $9500-line/cm$ 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 thicrzxek9 2d(s-x/sj ) onk, what wavelength is most strongly reflected at the center of the outer surface when illuminated normally ds2s(j-x) /zk9 rn oexby white light? Assume that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the dark fringes in Example 24–8 i4euvf2r+.ty o:xdvu,f k,fk v(z.:o f f the glass plates are each 26.5 cm long4(ft2,vfkvd:o.k u fr :xy.zvouf+, e ?    cm

  What is the smallest thickness of a sokoh8x uyz *o0;ap 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 yellowz0v ry r-) sqqp.wliu*52nga - ($\lambda\;=\;570\;mm$ is strongest) when white light reflects from it. What minimum thickness of coating $(n=1.25)$ do you think is used on such a glass $(n=1.52)$ lens, and why? $t_{min}$    nm

  A total of 31 bright and 31 dark Newton’s rings (not counting the dark )vvyvb) +2blt spot at the center) are observed when 550-nm light falls normally on a planoconvex lens resting on a flat glas vvy2blv t+))bs 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 ij1h o8ph0q ,-3x (0jshebcb xan Fig. 24–33. When light of wavelength 670 nm is incident normally, 28 dark lines are observed (wioq,h xb8h0 x( je-1bp0a hj3scth one at each end). How thick is the foil?    $\mu m$

  How thick (minimum) should the air layer be between two flat glaqf)9:z3jkd , kfx,emg ss surfaces if the glass is to appear bright when 450-nm light is incidqx3 k: z9,gkf, mfjd)eent normally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, suspected of being oqik(h1* 8acvu3 g1xka 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 eh7mtzpcv , aa vt( f6;5uau38$(n=1.36)$ 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. ow c(u s10pu(8dnu2c y24–31) is immersed in a liquid, the diameter of the eighth dark ring decreases from 2.92 cm to u1cy ucus2o8p(( w dn02.48 cm. What is the refractive index of the liquid?   

  What is the wavelength of th7xla vp*ho y,za.9c vmc lup*)-zmx77e light entering an interferometer if 644 bright fringes are counted when the movable mirroz pa xm lhxlou*zm7v.yp7,97)a vcc- *r moves 0.225 mm?    nm

  A micrometer is connected to the movable mirror of an interferometer. When thx7 b wm*0ccwe7s,ogf6 e micrometer is tightened down on a thin metal foil, the net number of bright fringecgw*77o cf,bxs ew0 6ms 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.h0 i97r/ rdvqx*klsf e1h(p f $M_1$ 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 interferometewpmn 58-4q- 6fckd4d-wnkl zbr (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 ob-n6qc pk4l8-5- zk4f dmnwd wf 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 oriev9-:wpz ejfr+ p g2xl;a9ko9s lgth58nted 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 anx,/pvtx z(uooc n9w68 air–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submerged in water ifr af sa ( 7uqc*rum0) 3,wztftyq.v3d7 the light is hitting the diawf,u s)(zc7. tq07*vq3a rr3d ytufammond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the light passing inlzq :t(q d ry72gtqh2+qt1nk)pd++ through them is a maximum. A+hynnq+rzdg7:2t+t q (lip2 q tq1 kd)t what angle should one of them be placed so that the intensity is subsequently reduced by half?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be nq, )ulvr,36e vah-hwod-,bj placed so as to reduce the inten ,,3nhwh-u-qa vrdb, o6 je)vlsity of the incident unpolarized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are orienckpfn/p l7i -5ted 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 orie5op*9 fea1akk nted 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 of lh e2+ohnx5y1f the surface of water for light coming from beneath the surface? Compare to the angle for total internaloh 1x 2l+ny5eh 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 passes through five successive Polaroid sheet8)sx; v xnr/wh mhntj7g 04l:ks, each of whose axis makt:0khnw g48/m nrvxx;s7) ljhes a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength fjuhhp y -2lhx0x5ir ,y s60(a$ 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 ink .k() +ssneg+zhv ;8og5oaamterfere withhv aez.ok o ksg)8 5;nms(+a+g the direct 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 separate sources passes through a diffraction grati 3r5evyz3k*b vng with rvk*b 335zvey$ 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 slis:n5a h2k;mqbp) sb7n ts 0.60 mm apart. The screen is 1.70 m away. A second sourcs knb2qn:b7h; as )5mpe of unknown wavelength produces its second-order fringe 1.33 mm closer to the central maximum than the 590-nm light. What is the wavelength of the unknown light? $\lambda_2$    nm

A radio station operating at 102.1 MHz broadcasts from two identical ajk0edj xni9 8 k3rw*i*ntennae 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 extending horizontally in both dik 3*n80xkj wjrei*d 9irections. 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 asj2dud 348qz b)/pg efn outside 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 pldg/4psjb e2qz3d)8 uf ayground outside the doorway.    $^{\circ}\,$ either side of the normal.

If parallel light falls on a single slit s(li7o; ry v2e lr0js3of width D at a 30$^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain beetle have a series of palx rh-y 0 fnk6 zx9g+:/ibzuk-rallel lines across them. When normally incident 460-nm light is reflected f- 6kiz/ bg+xkx y:h0rfn9zu-lrom 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 grating have if there is to b7*2 x6f- nbzj2mlghbt e no second-order spectru7mn*j 22g-b fz6l htxbm for any visible wavelength?   $ lines/cm$

Show that the second- and third-order spectfog* id;f3 g/fhqk2 3y-,jcs jra of white light produced by a diffraccsg3 - ,kqj2f*g/3j h yfif;dotion grating always overlap. What wavelengths overlap exactly?

  When yellow sodium light, k6 -oy(r)mc-qh uo/ yh$\lambda\;=\;$ 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 gkt*a7zhd - /tm 0otyi3rating with and the pattern is viewed on a screen 2.5 m from the gratmo 3i/y * 7t-zkhttda0ing. 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 mi yk. 1m-rkz)a9vy2tebnimum of 150 nm thickness o-eyvtbrk1z .m )ay92kf 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 have a choice for an answer?

  Monochromatic light of variable wavelength is incident normally on a t) 7kqwy 9hru gs*8uuk1hin sheet of plastic film in air. The reflected light is a minimum only7)8y9 w1uhgqu *uskkr 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 ,*k on0mlom2; b;hb8 a6jx ovsfor 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 betwi6garv)jy-zy 80j 5yleen two flat glass surfaces if the glass is to appear darkvyj-85g6i rly)aj0 y z 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 thin filxi 1k yu/jdmd2 ,z5c,lm 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 d1c dxi2j5,m kyl/z ,ucompared to the maxima and to zero.
24-30
24-36

  At what angle above the horizon is the+ilov-l g2 u,fnb)t ,o3vpt7u Sun when light reflecting off a smooth lake is polarized,ou,3 tg +uvlnp-bf o)27vlti most strongly?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as to reduce t d; ap.j31 bqgmi+(vyuhe intensity of the incident unpolarized lig .jyp+q1gv3 d(biuam;ht by an 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 are at rnfza r t c; 3gjwo 0j1snw-kpx.-4p*p4ight angles. A third polarizer is placed between the first two so that its axis mcsg tnoz pwwp-.3f k 4;j*-npa j0r1x4akes 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 vertical, at 30oo tw5p*b:pspbct 3+; e yq/odfk4: , r30fenf$^{\circ}\,$ 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 off8hymr z4+ez(zcnf - ; width 1.0 cm and is pointed at the Moon, which is af( yrh;enf4z 8z zm+-cpproximately 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 -olywl qc n-)8are each 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 w/w dlxm(wk, 8s6b p4w$(n=1.34)$ 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 k ua)nue()d6wf;1bnb 6.0-MHz radio waves in phase with each other. They are located at pointaedf;)(6bwb1 k n) uuns $S_1$ 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 twcn ap t.,89ts0tw/enmo wavelengths, 420 nm and 650 nm, enters a silicate flint glass equilater. e90m,8/ntp atwctsnal 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 fl+v)q2 6pcdsy wat 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