Does Huygens’ principle apply to sou y,2kpps,w.8iu :w gmknd waves? To water waves? Explain.

What is the evidence that light is enersu/mj5 d8j05 ng9m xcggy?

Why is light sometimes described as rays and sometimes as waveshqmhih levr) 4838 v:a 3to,wv?

We can hear sounds around corners, but we cannot see around cornes qkg 8p 5:y -w:cdip9fqkk12grs; yet both sound and ikk p829 d:wq5-: sqyggp1f cklight are waves. Explain the difference.

If Young’s double-slit experiment were suyhkzw6 zm* n+hb : )*k(xapw*pbmerged in water, how would the fringe patter* hx*bw*+ hamn6 zpzk(y p)w:kn be changed?

Monochromatic red light is incident on a double 4qc xw;sw15wgslit, and the interference pattern is viewed on a screen some distance away. Explain ;x514ws qcwwg how the fringe pattern would change if the red light source is replaced by a blue light source.

Two rays of light from the same source destruc9.h8jf6kub 9yp anq4et7 82jw vqxy/ ktively interfere if their path lengths differ 4j6yk k/b79ft8j9qhau xnw y8e. vpq2by how much?

Why was the observation of the double-slit interference pattern ms+ um5io r69lc;tspb, ore convincing evidence for the wave theory of light than the observation of diffractiop+ 6li c9;bs,5muo rtsn?

Compare a double-slit experiment for sound waveap17aopbbpf*-* n g5rpw4 /3dnmjo: js to that for light waves. Discuss theo/f-apb4jnp o7n b d*rw *p5:pmg3ja1 similarities and differences.

Why doesn’t the light from the two headlights of a distant car zz1 .m feg ):d(cqzgdkb;-x x8produce an interff e-gdkq1:b z;)xmx zz(g8d.c erence pattern?

Suppose white light falls on the two slits of Fixk8;zp hg h:g46 y/ktmrv j6p)g. 24–7, but one slit is covered by a red f hhmg86kx;zgyrp/ : 4 jvtp6)kilter (700 nm) and the other by a blue filter (450 nm). Describe the pattern on the screen.

When white light passes through a flat piece of wind9eu8 n nn0mg7aow glass, it is not broken d nu8m79 0nenagown into colors as it is by a prism. Explain.

For both converging and diverging lenses, discuss how the focal length for red 2 qrwgh3*m7v qlight differs from that for violet li3v*7g 2qq rhwmght.

A ray of light is refracted t-1bo koag ok8 :6wzkp(fp8 lfpxh/k) ,hrough three different materials (Fig. 24–55). Rank the mate 6/f,1-pk foz )wakl :(oo px8kkg8hpbrials according to their index of refraction, least to greatest.

Hold one hand close to your eye and focus on a distant light sourh**;kh6-gmyv 8yxxy 5mts1 ozce through a narrow slit between two fingers. (Adjust your fing x-8vzymtyhksmh5yx 6; og1** ers to obtain the best pattern.) Describe the pattern that you see.

What happens to the dkugn5 g -.en(hiffraction pattern of a single slit if the whole apparatus is immersed in (a) water, (b) a vacuum, instead .eg (gn5un h-kof in air.

For diffraction by a single slit, what is the effect of increasing (a)j +lejgb8cw-i)3 qg, o2qn6d m the slit width, and (b) the wa8+l6m bieqcgg q-d ),w2ojn3 jvelength?

What is the difference in the interference patterns formed (a) by two slits .h /zi:b3prz n$^{-4}\;cm^2$ apart, (b) by a diffraction grating containing $10^4lines/cm$?

For a diffraction grating, what is the advantage of (a) m0 c3ji+nkp+*6jhw8v; ju0af v 0iyiboany slits, (b) closely spac+uo;kf*v 60ihvb3pjj0n +0i yc8wj ai ed slits?

White light strikes (a) a qqd3. c ;bp- brcu. m/za(jr)ndiffraction grating, and (b) a prism. A rainbow appear- (d nrrm./ u)bpz.j;abcqqc 3s on a wall just 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 400 nm and 700 nm, i1t vihfjg/3 y1ju9db tv2y: c2ncident normally on a diffraction grating, for what orders (if any) would there be overlap in the observucfv:9y v1y2dit/bht1g 2jj3ed spectrum? Does your answer depend on the slit spacing?

Why are interference fringes notnioq* pk4m.nu i d74(diceable only for a thin film like a soap bubble and not for a thick piece of glass, say?uq4 mdi(.d7ni p*no k4

When a compact disk (CD) is held at an angle in white light, the hr- wjgps43j(9k 9mk mreflected light is a full spectrum (Fig. 24–56). Explain. What would you expect to see if monochromatic rk(mk4 pg9j3sj9m wh- light was used?

Why are Newton’s rings (Fig. 24–31) closer togmry; 1qa*nizo -m..t / fcs7glether farther from the center?

Some coated lenses appear greenish yellow when seen by refl wj(1n)i- omuvr ayji s6 rikj)1b(*5cected light. What wavelengths do you suppose the coating is designed to transmabsjmu ))i r*oi5v y6c11kr(-( ijjwn it completely?

A drop of oil on a pond appears bright at its edges, waw24f p.ol cr52+xg achere its thickness is much less than the wavelengths of visible light. What can you say agl.c2aap c 2xr5fo+w4bout the index of refraction of the oil?

What does polarizatio6fc78w 5udawyyn7l .qn tell us about the nature of light?

Explain the advantage of polarized sunglasse0ib6k,vcnwtzq2qt ;j, 8fs ee 5.h;pzs over normal tinted sunglasses.

How can you tell if a pair of sune wrz*n2 he.q-ez 6pi i)+-atkx+q vq.glasses is polarizing or not?

Two polarized sheets rotated at an angly8zd *w+av t.r hpo(3h+ u)gy,9wzfoke 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 Eart32pdsyoh+qvv:e+w ch+ijk,+ h had no atmosphere?

If the Earth’s atmosphere were 50 times denser than it is, y4*-nwtb sjeh: w /bg3would sunlight still be white, or would y*wb3s:hwg jen t/-4b it be some other color?

  Monochromatic light falling on two slits 0.016 mm apart produces t wxcl;dcn ;;l2yzc9l4he fifth-order4;9czyc2xln l ;dl ;cw fringe at 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 obsert*n nt5,f(qbx ved 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 0.048 mml4 z/zp(qi /4vd0zmxw apart. Successive fring ziqx 44/m p0dlz/wv(zes on 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 from a He-Ne laser, with a waveleng5z*k*q t)x/qb hbmil7th 656 nm, falls on two very narrow slits 0.060 mm apart. How h7qq)k5l b/ztb*mxi *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 anv6 plizg,rfrf) 1s:;i interference pattern in which the fourth-order fringe is 38 mm from the central fringe on a screen 2.0 m a1,sff:pzliv;i ) rgr6way. What is the separation of the two slits?    mm

  If 720-nm and 660-nm light passes through two slits 0.58 mm apart, how fa1o1ezl,n0 qp: enk(wjr apart are the second-1ln(,qen:0jo e zp1k worder fringes for these two wavelengths on a screen 1.0 m away?    mm

  In a double-slit experiment, it is found the,9(sqb9-9ali/:adki f m m ceat blue light of wavelength 460 nm gives a second-order maximum at a certain location on -bi, se(me9:afik9 acm9 ldq/ 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) oqwx zz4,,w h;p1xxr pass through 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 be little or no wave1r, hx;xoz p)q 4xwzw, action?

Suppose a thin piece of glass isxn,q19 o-nlbw e2d,qz8 *0a5ytcwdyr-m+e dt placed in front of the lower slit in Fig. 24–7 so that the two waves enter the slits 1tnrwm le wdtd9q,qyx+*1eb-, a25 o8ndz-cy080$^{\circ}\,$ 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/cpf69q3g.p 4 ewtblrght 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. 9/p .ce4f3wlg tq6bprHow 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 light. Find tb9.ca qyvjeb;z o::o 8dfkm/*he distance between adjacent brightjdb8/ ;yvka f o9eq .:bczmo:* fringes on a screen 5.0 m from the slits.    mm

  Light of wavelength 480 nm in air falls on two:vr;0 poxfaw9-zr9 xn 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=1.6nz9 oo 3yg)x7 jogv(j60) 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) th7 6y 3 j(9zovngogjx)oickness of the plastic?    nm

  By what percent, approximately, does the speed of red lightw yh vrr0.nq-32 ubf3w (700 nm) exceed that of violet light (400 nm-rwf33rnqw2y0.u hb v) in silicate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece of glashfsz:gb pwm (bg:4d* :s at 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 containit. /) wfpas1f.tfe6p)puiw/ zng 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 full angular width o8m v.l+u p-c2u)ft/ ns4jlfbmf the central diffraction peak4tf+ 2snlf m)8plubjcv/-um. ?    $^{\circ}\,$

  Monochromatic light falls on a slit that isqn8/:h-s.up x uyos f- $ 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 sl8 hao9+e z.ihqw8n,0wzl:e;h3qbf j qit 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 illalj3p8m5 0kc b1d .phkuminated by 450-nm light. What is the width of the central maximum (in cm) in the diffraction patt k5h0a dlbm81jck.pp3ern on a screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm falls on a slit. If the angle betwd.eik /0yfp.mh- 5 4 ak-kqteceen the first bright fringes on either side of the 5akh-kqkft/ e.de 04.pcm i -ycentral maximum is 32$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central diffraction peak onh9dse( xybzl+de* sb6vl(:(b a screen 2.30 m behind a 0.0348-mm-wide slit illuminated by 589-nm light? ezd xyb:*eb d+s(bh vl9l(s( 6   cm

  When blue light of wavelength 440 nm falls on a single slit, the first vi,heo/rya o8te 5neo746m5i dark bandsrmvie 5,5 oto6i 8ehy7no4/a e on either side of center are separated by 55.0$^{\circ}\,$. Determine the width of the slit.    $ \times10^{-7 }\;m$

  When violet light of wavelength 4r mo-/azh43 h 8xzl6lc15 nm falls on a single slit, it creates a central diffractiohr8zm/l c-z h3aol46xn peak that is 9.20 cm wide 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 diffraction maximum is 4fx guvmb 5szjqk(;5- g c0;q/t.0 cm wide on a screen 1.50 m away, what will be the width of the diffraction maximum for light of wavelength 420 cg/mqgkvj 0 -;qz(x;sut fb55nm?    cm

For a given wavelengs1ix/zfp;uk w:zf1 p 2th $\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm light prod tpmgar52* 20x.f o p+km*:wdewed(vzuce a second-order maximum when falling on aw 2efrkz(a 20t *. p:medwmdov*px g5+ grating 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 third-orde k8li1o)hw rkhh2wo*tn (s80 fr occurs at an nh1(k o wh2 tw*ri0o8fls hk)818.0$^{\circ}\,$ 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 ofhp /0-:q tsasl e/k(wa 589-nm light falling on a diffraction grating is observed a aksh/qlse/0( -p:t wat a 15.5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction gratind - pkyz7k08o9fzo1bbdrt 0i 4g 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 4p8o-vlu(7fh-d+m+wn-u4t pzr v k w mon 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 n s:-;gf u+mkethat can be seen if a grating with 6000 lines per cm is illuminated with 633-nm laseem;ug -+kfn:sr light? Assume normal incidence.   

  Two (and only two) full spectral t0)ejsq8r3e7 (ojt 6bo*v s (rll-so korders can be seen on either side of the central maximum when white light is sent through a diffraction grating. What is the maximum number of lineo kbresej)6 o((-lsjo*7l08t 3srvt qs per cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containing wavelengths from 410 nm to 750 nm falam2+ )l i clrb:2vqgilw3yd6 .ls on a grating with : 3a2vm+qbry)6il gwld 2li c.$8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which produces monochromatic light of a known wavel.5ky uc 1mc infxcto m)1fm:ibt8f 218x/pnj2 ength $\lambda\;=\;6.328\times10^{-7 }\;m$ 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 mfzj ip2poocq *q 8cl:;orm)mtpbs8l 10j5d8 5easured 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, 5lf( kn5k1gk xf kjj);what wavelength is most strongly reflected at the c )ng1xkf;l k5jj5kf(k enter of the outer surface when illuminated normally by white light? Assume that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are thh-jqnkj s1s t7k0 s8rf)2kzg-e dark fringes in Example 24–8 if the glass plates are each 26.5 cm long? 0 k8nsj s tfjhg)qsr7- kk-2z1    cm

  What is the smallest thickness of a soap fill6r oik/0zh 9am $(n\;=\;1.42)$ 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 -i*srcfcxuc2j61e :gq p3b j)(vpe7z($\lambda\;=\;570\;mm$ 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’g: y myjco:,d7s rings (not counting the dark spot at the cgm7 do,c:yyj:enter) are observed when 550-nm light falls normally on a 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 flj ;.cl, t,f9x 8usnmnvat glass, as in Fig. 24–33. When light of wavelength 670 nm is incident normally, 28 dark lines are observed (withlv,fm8sxnj;c u,9 tn. one at each end). How thick is the foil?    $\mu m$

  How thick (minimum) should the air la/6 wyla*d k5yiyer be between two flat glass surfaces if the glass is to appear bright when 450-nm light is incident normall*/5adkli ywy 6y?    nm
What if the glass is to appear dark?    nm

  vA piece of material, suspected of being a stolen diamws wm)x 137xwne,hq8s ond $(n=2.42)$ 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 alcoh ghahg8l0ztx2j c)2v 1ol $(n=1.36)$ 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 diame oon-d. dn2:nuter of the eighth dark ring decreases from 2.92 cm to 2.48 cm. What is the refractive index of the liquin -oudo:n2.ndd?   

  What is the wavelength of the light entering an interferometer if 64ul;xqu1-hx jnj- h-k :4 bright fringes are counted when the movable mirror moves 0.225 uq-hnj- k- ;1lj:hx xumm?    nm

  A micrometer is connected to tfv:6 b2.l aslehe movable mirror of an interferometer. When the micrometer is tightened d:bs lla26v.ef own on a thin metal foil, the net number of bright fringes that move, compared to the empty micrometer, is 272. What is the thickness of the foil? The wavelength of light used is 589 nm.    $\mu m$

  How far must the mir2hc c)n9n.rqok 5 *yk,ui0 ihtror $M_1$ 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 through a smallf0j0xz*wtg t*6 pmn9p glass container containing a cavity 1.30 cm deep. When a gas is allowed to slowly fill the container, a total of 236 dark fringes are counted to move past a reference line. The light used has a wavelength of 610 nm. Calc90 z p6gxftn* wm*t0pjulate the index of refraction of the gas, assuming that the interferometer is in vacuum. $n_{gas}$

  

  Two polarizers are oriented at 65vb3r qr+36sl- :d xbv2otj5 ba$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s angle for an air–glas9lb hk 8/f pwbcl7ud.(s $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submerged in water if the jh;cct4kvuc0ye7d)lg g +t 0fg732qb light is hitting the dg cg0dj;l2k c3u v74e 0h+qb gctytf7)iamond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are alignedo. 6ur3zq8 nh hd11qe+5uoxw v so that the light passing through them is a maximum. At what angle shdhh .w re+ 53qunozo68x1uv 1qould one of them be placed so that the intensity is subsequently reduced by half?    $^{\circ}\,$

  At what angle should t8 4fk8qbpt 3bfhe axes of two Polaroids be placed so as to reduce the intensity of the incident bpf bf t834qk8unpolarized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are ori4;3ujt fhesx yzs9z2gzp- 2p6ented 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 or /( kbezsccasi 6xx-*.nvqk.9iented 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 off the surface of watjltaw syi/.j 89l1e-hkv21p;t - thi ler for light coming from beneath the surface? Compare to the angle for total internal reflection, and to Brewster’s angle from above thet19t1- ;t ll -y 8.2lewp/jahhvki sij 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 sheets, each o8,zp zu/mv5:rkpiyxdmrb va *6v n 7: z1fd6/gf whose axi:5 ,pu vzdga7yk/ v1p*mdnr : rbxm6vzf68z /is makes a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength xggp*naki6bi+b 2g .9$ 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 radiosj 0mjic:zhcv4: 1:x9qv 1pss waves reflecting from mountains or airplanes can interfere with the direcsx pcjvs:h9q14 z j1s :0cimv:t 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 sourcea5)l(varwy8h aw j3a+ s*ox3js passes through a diffraction grating with lax38owj+sw a)r(3 h ajay5*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 aparx- 7zkc 94spst*eatt5t. The screen is 1.70 m away. A second source of unknown wavelength produces its second-order fringe 1.33 mm closer to the centrtes ck9az st7p -*5tx4al 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 twzp293zj,xou i o identical antennae at the same eleva 2p3iou z9j,zxtion 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 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 ur ;kvh; .vvusfr )f3.m wide, and blows a whistle s; v;. r.uv)3krffhuvof frequency 750 Hz. Ignoring reflections, estimate at what angle(s) it is not possible to hear the whistle clearly on the playground outside the doorway.    $^{\circ}\,$ either side of the normal.

If parallel light fa9zn( 3yerrm 26s)zkeg lls on a single slit of width D at a 30$^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain beetle hiot4a6.v zphh.km* s ,ave a series of parallel lines across them. When normally incz,k.pmv.a 6 hito4*shident 460-nm light is reflected 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 cenzryjyg* )-* litimeter must a grating have if there is to be no second-order spectrum for any visible wav-**rj iz)y gylelength?   $ lines/cm$

Show that the second- and third-order spectra of w meml sh8m- q7ua z5fip6(o1o1hite light produced by a diffraction gratinghmmsez- 1ql1aop5 7( 8o6umif always overlap. What wavelengths overlap exactly?

  When yellow sodium light, : ru5q z+p:gbx3n)qbbe -ti+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 1 vsqor*cmu40 a diffraction grating with and the pattern is viewed on a screen 2.5 m from the grating. The incident light beam consists rq1m 4*vou0c sof 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 ref 7mv pwhi39;;i*hqh1 n jtz.gfraction of a clear material if a minimum of 150 nm thickness of it, when laid on glass, is3qg;mhpt nf.wh 1h9iz 7vi* j; 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 wavele-;u)m v9dlnknt , h0o-x0+ j y4bmpxxwngth is incident normally on a thin sheet of plastic film in air. The;tx) xjdpvn9m+4lnwy 0xuk-hb -0om , reflected light is a minimum only for $\lambda\;=\;512nm$ and $\lambda\;=\;640nm$ in the visible spectrum. What is the thickness of the film $(n=1.58)$? [Hint: Assume successive values of m.]    nm

  Compare the minimum thickness needed for an anti-reflect lu 18x;ckrt) irbz6ll(.kic ,ive 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 ,q7o8yqx (n +h qkhx7dtwo flat glass surfaces if the glass is to appear dark when 640-nm light is i(h +n7x8 qqhyq,xkd 7oncident normally?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the light transmitted through a thin film layered ony*5wpy z7v kkb3 bd-y,3bkz-v 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 ckb33*y-dkz5w by 7pz, kvvb- yompared to the maxima and to zero.
24-30
24-36

  At what angle above the horizon is the Sun when light reflecting off a smooth ex35 bjobpjr-8ir4 p2lake is polarized mostj2i r po58jebxpb r-43 strongly?    $^{\circ}\,$

  At what angle should the axes of two Po)v+/::ofxy pto jjj *rlaroids be placed so as to reduce the intensity of the incident unpolarized light by an additional j:oro+/y:t*jx jp )f vfactor (after the first Polaroid cuts it in half) of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light falls on two polarizer s.378s *d2 rbwvvuamp-tu2zt h wa(h4fheets whose transmission axes are at right angles. A third polarizer is placed between the first two so that its axib -(w.t 4w8 vu hhpfda m*7zusr2vt23as 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 theirzb)53dw9y z9mjysln 7fcay*56r4sm h 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 wijrfc3moplb* 2 lv v+ph4zg9(2dth 1.0 cm and is pointed at the Moon, whicol lvg2 3jbm4+pp2cr* hf9zv( h is approximately 380,000 km from the Earth. Assume the laser emits waves of wavelength 630 nm (the red light of a He-Ne laser). Estimate the width of the beam when it reaches the Moon.    km

  A series of polarizers are each,h)dw;to7 dee 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 ,be*dvvudtnvvy v r3x73 ,ry-d g041:f 4xz yi$(n=1.34)$ 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 phase with each op tx xd*+9oa3vther. They are located at points o avtx 3dx+p*9$S_1$ 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 wavelengg 78jp m/1sjrlr0( wnh(she446z uqq.ubv p:yths, 420 nm and 650 nm, enters a silicavn(:brjrjg w 8z( s uy/h4m.4 php710lq6sqeute flint 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 onecu2bjgknvgo-s 1 n6wsf 4,(4y 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