Does Huygens’ principle apply to sound waves? To water waves? Explain.: l(ol7d0u,rpqi; z pa

What is the evidence that light rh.o e:7eqbe+q 64jko is energy?

Why is light sometimes described as rays and somjp 0*krydo1sl+, (nzob u9 9vmetimes as waves?

We can hear sounds around corners, but we cannoth n. dzdg7 .( mkc2han-66hxkc see around corners; yet both sound and lightk 2(cga.. khnmxzcdhn-7h 6d 6 are waves. Explain the difference.

If Young’s double-slit experiment were submerycv26s zm w vmf1+b(zi-bo:e*ged in water, how would the fringe pcy6m bsviwov: f1*(+b2-z e mzattern be changed?

Monochromatic red light is incident on a double slit, and the ing2vyme1 xr:m 2terference pattern is viewed on a screen some distance away. Explain how the fringe pattern would change if the red light source is replaced by a blx 21vry:me2mg ue light source.

Two rays of light from the same source destructively interfere if theoq:0 1gq o mv/+7vri.udxn+ycir path lengths differ by how muchcvgo+viy/rq:q 0d7 mnux o1+ .?

Why was the observatiof9yjybxp7i m:* -l*jqn of the double-slit interference pattern more convincing evidence for the wave theory of light than the observa*j mpbi* fj7-yxyl9 :qtion of diffraction?

Compare a double-slit experiment for sound waves to that for light waves. Djaxeh226l a:q;o*c gxiscuss the similarit22;haaqog cl :x*e6xj ies and differences.

Why doesn’t the light ;0,jttjzk.l6s2 t;lknshuw .n kp(-w from the two headlights of a distant car produce an interference pattew.tl.n0tj k u;,th p; wsknjz(6 s2-lkrn?

Suppose white light falls on the two slits of Fig. 24–7, but oner 8*t,ws liy.f cuqnb64qc3z rw)+*ix slit is covered by a red filter (700 nm) and6) tq8snqf.ly rw4+b,iu*z *x rci3 wc the other by a blue filter (450 nm). Describe the pattern on the screen.

When white light passes through a flat piece oj7c8qjx c r7+df window glass, it is not broken down into corjx8c 7cqj7d+ lors as it is by a prism. Explain.

For both converging and dip.wy-7 :)vdze+0gkdvhr 6yqbverging lenses, discuss how the focal length for red light differs from that for violehyw )v+0kdr .-ygzdb6e 7pqv:t light.

A ray of light is refracted through three differe g(u/)8orn ijlnt materials (Fig. 24–55). Rank the materials according to their index of refraction, lea lr/iugo8)j (nst to greatest.

Hold one hand close to your eye and focus on a rbm.s(eo41r; 8 w0.gjpcq9xngvn6wi distant light source through a narrow slit between two fingers. (Adjust your fingers to obtain i6nvxg 0qn..er 9o8wp(wsb4cgr1; mjthe best pattern.) Describe the pattern that you see.

What happens to the diffraction pattern of a single slit if the w6 aku 1yafdia-1 z1k uw+emv60hole apparatus is immersed in (a) water, (b) a vacuum, insteauza f661ud - eakm y+kwv110iad of in air.

For diffraction by a single slit, whav27cugx(i 2-r3 fgxg qt is the effect of increasing (a) the slit widq2xgg-237r fgc vu(i xth, and (b) the wavelength?

What is the difference in the interference pncvcq-a:ts /yx ml(rde-1b 2-2h;dgjatterns formed (a) by two slits $^{-4}\;cm^2$ apart, (b) by a diffraction grating containing $10^4lines/cm$?

For a diffraction grating, what is the advantage of (a) many slia(-.if3td mx)xk io h,jt,4ckts, (b) closely spaced kk4mif. 3,)-,dicjxhotxt ( a slits?

White light strikes (a) a diffraction grating, 0z3azx dd /6pmand (b) a prism. A rainbow appears on a wall just below the direction of the horizontal incident beam in each case. What is the color of the top of the r3 pda z6m0/xzdainbow in each case? Explain.

For light consisting of wa3-ds7d upj12dlo m- gcvelengths between 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 -p ol c1s7d3-dmuj g2danswer depend on the slit spacing?

Why are interference fringes noticeable only for a thin film like a soa2a f;t9(ddd:vx4asw)adv i5 up bubble and not for a2)d4a( 5t aw s:x9dv;vdfdaui thick piece of glass, say?

When a compact disk (CD) is helc+doiamvp i:: r,tm44 d at an angle in white light, the reflected light is a full spectrum (Fig. 24–56). Explain. What wouocv:t4 mm+4 r :ida,pild you expect to see if monochromatic light was used?

Why are Newton’s rings (Fig. 24–31) closer together farther 5nsxhl +)nsuo3*.t2xqjtj2tau s l 93 from the center?

Some coated lenses appear greenish yellow when see3ju*di: ;rvg -di gyx2n by reflected light. What wavelengths do you suppose the coating is designed to transmit completelyy :g-r*uid;xjgi d23v ?

A drop of oil on a pond appears bright at its edges, where its thickness dc+ (7f luv)e/c0annais much less than the wavelengths of v a(nce)dulcf0 / 7vna+isible light. What can you say about the index of refraction of the oil?

What does polarization tell us aboup/sq+gdj c/e +t the nature of light?

Explain the advantage of polc 9fo,tas n9r.0l :68lnws zkdarized sunglasses over normal tinted sunglasses.

How can you tell if a pair of sunglasses isa 6ceas c q 3bh,+y0r(sidz5(v;pk 9we polarizing or not?

Two polarized sheets rotated at an angle of 9wmqf/ ixbkv:-g +7ev,ns3ns30$^{\circ}\,$ 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 Eart d+qmwlfn*i ..h had no atmosphere?

If the Earth’s atmosphere were 50 times denser than it is, would sunlight sc 71owarb k :;hg0x:; tnkt*ewtill be white, or wou t xhgt0rn;k:wbe awok17*;c: ld it be some other color?

  Monochromatic light fallzg73asy6ucqg-96rb rc u,f( oing on two slits 0.016 mm apart produces the fifth-order frin 6 s g-y7fuqc 9aurg3b(or,6czge at an 8.8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 610 nm lightqqim1j( m5z*g 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 twouujv;h pk0 b+x1 .mr(g very narrow slits 0.048 mm apart. Successive fringes onrv(upb 0+.ukx1ghj m; 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, w(xb5b7vcw2jrl 46g lvith a wavelength 656 nm, falls on two very narrow slits 0.060 mm apart. How far aparv v(6g lwlxc2br 7j54bt are the fringes in the center of the pattern on a screen 3.6 m away?    cm

  Light of wavelength 680 nm falls on t+be+u,nd- oi ywo slits and produces an interference pattern in which the fourth-order fb iou,+-y +nderinge 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 0da2ncavi+ atyim42za:t6 4+ m .58 mm apart, how far apart are the second-order fringes for these two wavelengths o+4itya: td4amm6ca a v+ izn22n a screen 1.0 m away?    mm

  In a double-slit experiment, it is found m8zk0 b jsx2i n5jk6uj0-y:el that blue light of wavelength 460 nm gives a second-order maximum at a certain location on the screen. kn5s6j2 ikuy- 0ejzb:8j mx0lWhat wavelength of visible light would have a minimum at the same location?    nm

Water waves having parall/gy021oy g hpmel crests 2.5 cm apart pass through two openings 5.0 cm apart /yggo 0m 2hp1yin 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 wave action?

Suppose a thin piece of glass is placed in front of the lower sl d6 nvhql9c24*+7 0mwyfn 68hne asiabit in Fig. 24–7 so that the two waves enter the slits 1809*6cm ynq sha2 wn bnf4id7h0lv68+ae$^{\circ}\,$ 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 wavelengm a2m* fynn(d9(:h vseth 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 thennm* yh: nd2veam(s(f9 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 illu5j7l w a2tq7aominated by 544 nm light. Find the distance between adjacent7j2q o75l aawt bright fringes on a screen 5.0 m from the slits.    mm

  Light of wavelength 480 nm in air falls onnc7 7hg6bn,juw:s7u.z h9c sc 9va6sw two slits $6.00 \times10^{-2 }\;mm$ apart. The slits are immersed in water, as is a viewing screen 40.0 cm away. How far apart are the fringes on the screen?    mm

  A very thin sheet of plastic (n=1.60) covers),j3q32) 6tbcbstxgf 4ck;id4tjc c xrd/l* j one slit of a double-slit apparatus illuminated by 640-nm light. The center point 2d/gxfb*k6j )ij3r ;)btl3 4 xdq4 c,c tjctcson the screen, instead of being a maximum, is dark. What is the (minimum) thickness of the plastic?    nm

  By what percent, approximately, does the spen das k:;q+2im5u;wpmed of red light (700 nm) exceed that of violet light (400 nm) in silicma pq kmidwus2n;;5+: ate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece ofwz8i7mr wk lug6 :8jd.hf1 2lzta*ra- glass 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 containing two wavm0:2r evpha-hf7;4i nvmfj 5 xelengths, $\lambda_1\;=\;450\;nm$ 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.(jps 3 dvmwa(kr-22z z+ff+:gc1d i ez0440 mm wide, what is the full angular width of the central diffraction zz1mwdcg+d2 k(sazv3ejri +:f2 p-(fpeak?    $^{\circ}\,$

  Monochromatic light falls on a sl:rwf4dg44i0 t,2qaqna3/( r xa4ab l)a oqaggit 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 slit thatdw82d.r/ggw n u3wuo ; 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 widb:sy;r;mi i4c8 t x3mle is illuminated by 450-nm light. What is the width of the central maximum (in cm) in the diffraction pattern on a scrs8b r m3xc: l;ytim4;ieen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm falls on a sprv ,tq)a7v em54zy 5wlit. If the angle between the first bright fringes on either side of the central maximum is 32 pyv)wz4e 7mq55avtr,$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central diffraction peak on a screen 2.30 m behind a 0.0xu,+q/sjd8 s1vf cje08h q/ jq348-mm-wide slit illuminated by 589-nm lisd8ef0jqj 1su qc8jx, //+vqhght?    cm

  When blue light of wavelength 440 nm falls on a single sli hb/aa:upuw 2)3ygqd -ge8 3qmc2-jdkt, the first dark bands on either sidy/g -3 wj2 h q2u)paamgedu8-b3k:cqd e of center are separated by 55.0$^{\circ}\,$. Determine the width of the slit.    $ \times10^{-7 }\;m$

  When violet light of wavelength 415 nm falls on a single slit, it creates* eb:i8vb +hef a central diffraction peak that is 9.20 cm wide on a bebv8h+*fie : screen that is 2.55 m away. How wide is the slit?    mm

  If a slit diffracts 650-nm light so that the diffp a,kdpu8g 1o7y( fe7uraction maximum is 4.0 cm wide on a screen 1.50 m away, what will be the width of the diffraction maximum foya7(p8duke, o1pgf7 u r light of wavelength 420 nm?    cm

For a given wavelength d ,;lw;b:q3rwn79gie atwqs . $\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm light produc4jp ,pa- 9 apceers*-q ) vxyt9c(onz8e a second-order maximum when falling on a grating whose slits are aza8,py en9c pq xv erps c(o*-j9)4t-$1.45 \times10^{-3 }\;cm$ 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 hiqx wpy ip5:1+9if 5zbave if the third-order occurs at an 1yp x+: 9p5i1ibi5qfwz 8.0$^{\circ}\,$ angle for 630-nm light?    $ \times10^{3 }\,lines/cm$

  A grating has $8300\;lines/cm$. How many complete spectral orders can be seen (400 nm to 700 nm) when it is illuminated by white light?   

  The first-order line of 589-nm light f9f )xc4 yfhfw3alling on a diffraction grating is observed at a 15.3wfy)x4h9f fc5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction gratinuxg8 xqh(q eq(p06cw: g 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 a p1y0o *6r(iasn lel* s$9700-line/cm$ grating is revealed to contain three lines in the first-order spectrum at angles of 31.2$^{\circ}\,$, 36.4$^{\circ}\,$, and 47.5$^{\circ}\,$. What wavelengths are these?
$\lambda_{31.2}$    nm
$\lambda_{36.4}$    nm
$\lambda_{47.5}$    nm

  What is the highest spectral order that can be seen if a grating with v2.:a zcj33 nf-mmyny6000 lines per cm is illuminated with 633-nm laser light? Assume normal incidaj.:ym 3fznv 2m-cy3nence.   

  Two (and only two) full spect r dqbd+ ;;t3owbz-:edral orders can be seen on either side of the central maxbd3 ;ddezq-wto + b;r:imum when white light is sent through a diffraction grating. What is the maximum number of lines per cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containing wavel saem */bzkvs1-rj .g/engths from 410 nm to 750 nm falls on a grating with v1m/.zsjg-/sa kb er *$8500\;lines/cm$ 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 w t rr5c.3d,fsyavelength $\lambda\;=\;6.328\times10^{-7 }\;m$ 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 mea: x ak0txya65psured 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 wapfecus/n: t j5xs7*7w1 h/ zocvelength is most strongly reflected at the / hc5j: px7/7u *te sz1fcnsowcenter of the outer surface when illuminated normally by white light? Assume that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the dark frinyhf :w1z*/ .8poiuz3b yuwi 4vges in Example 24–8 if the glass plates are each 2 vyi*/z:uuowy 1fp38ziw. b h46.5 cm long?    cm

  What is the smallest thickne *ukjfko-yci;g0 6 ii+ss 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 yvzq.nm lz9;:pellow ($\lambda\;=\;570\;mm$ 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 (n m4ta .m-fn6hkot counting the dark spot at the center) 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 kh-fm6atn .4mthe edges?    $\mu m$

  A fine metal foil separates one end of two pieces of optically flat glass, as 5hg nl,r,l7d:rim g-4q rrpu/in Fig. 24–33. When light of wavelength 670 nm is incident normally,r r:,rr-qdu hlmn,l/g47 5gip 28 dark lines are observed (with one at each end). How thick is the foil?    $\mu m$

  How thick (minimum) should the air uqsqd.o qone6a6j n*p- ),,yc layer be between two flat glass surfaces if the glass is to appear bright when 450-nm light is i qoo cay-6*6,sju qnp,ed)nq.ncident normally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, suspected of th clca:xw/g +33 4mjnbeing a stolen diamond $(n=2.42)$ is submerged in oil of refractive index 1.43 and illuminated by unpolarized light. It is found that the reflected light is completely polarized at an angle of 59$^{\circ}\,$. Is it diamond? ----待选择----yesno 

  A thin film of alcoholg:o uh wa3lz82 $(n=1.36)$ 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 immerswh47.g u9bj wnt8xlz 4ed in a liquid, the diameter of the eighth dark ring decreases from 2.92 cm to 2.48 cm. What is thbx47. nt jg849ulwwzhe refractive index of the liquid?   

  What is the wavelength of the light entering ar ahl, v9rt3:,b ,;llcbjsw f)n interferometer if 644 bright fringes are counted when thel3cwbratl) ,v;:,rl s, 9j bfh movable mirror moves 0.225 mm?    nm

  A micrometer is connected to the movable mirror of an interferometer. When the b3pnz/ v g2k;vmicromk b/nv2 3pg;vzeter is tightened down on a thin metal foil, the net number of bright fringes that move, compared to the empty micrometer, is 272. What is the thickness of the foil? The wavelength of light used is 589 nm.    $\mu m$

  How far must the mir9p syvu(:dps1sh3 /ne ror $M_1$ 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 smag8hjq flf/o(i , cam08eju d5i-m,x) nll 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 coji /c of 8 xf0d,8iq5hjnmae,)mglu-(unted 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 orien ;:eng0hatz1 ujzgfjw639t+y ted at 65$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s angle for an a3b6va498 u.xs)vpbkt x*wb gg3cyt 4tir–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submerged in water if the light is6 a+1wvtue/bc hittinva+ b etu6c/1wg the diamond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that n6j8 v; kpgi8qf*1 wbwthe light passing through them is a maximum. At what angle should one of them be placed so that the intensity is *i1 gfwk bp 6v8q8wj;nsubsequently reduced by half?    $^{\circ}\,$

  At what angle should 3( nuq.cgyyx6e7; wr a6w 2imon1g0ogthe axes of two Polaroids be placed so as to reduce the intensity of the incident unpolariu 621(wyrmai . 63y0 x;nogw7ngoeqgczed light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are oriented at aafoje/32)oi40$^{\circ}\,$ 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 w pj3,b:.4rt-lx cyou o+csr138.0$^{\circ}\,$ 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 watw c7 2lcze fp.pw;g.k+er for light coming from beneath the surface? Compare to +gp7 2wkwlezc. pf;c.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 passes through five suc7*j o l(gp;hkacessive Polaroid sheets, each of whose ax;ap*j7gk (ohl is makes a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength 9 fsj- pchhrlh0 rxv *r-8s1g6$ 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 reflo6uy:bc jdp3s b3 a-gd,x8v-fecting from mountains or airplanes can interfere with thebp-63f8sdc,j g-bu:xa yv d3o 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 throu -+b fvd/5 *5aruk5i4vuu/eiid1a s ujgh a diffraction grating with a5 r/*i4e +v1iki/jfs5 vd5u-abu duu$ 3.00\times10^{5 }\;lines/m.$ The wavelengths of the three lines are $ 6.56\times10^{-7 }\;m$ (hydrogen), $ 6.50\times10^{ -7}\;m$ (neon), and $6.97 \times10^{ -7}\;m$ (argon). Calculate the angles for the first-order diffraction lines of each of these sources. $\theta_{h}$    $^{\circ}\,$ $\theta_{n}$    $^{\circ}\,$ $\theta_{a}$    $^{\circ}\,$

  Light of wavelength 590 nm passes through two narrow slits 0.60 mm apart. The ledwox;9z) aqld h6 80screen is 1.70 m away. A second source of unknown wavelength produces its second-order fringe 1.33 mm closer to the centrala ;lohz q l8w0d9d6)xe 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 fromo9 we4sj -r:bd two identical antennae at the same elevation but separated b4 wsed9 j-r:oby 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 m wide, anpl du,i uldi,( ;3ny l /;emp-bjcj7f6d blows a whistle of frequency 750 Hz. Ignoring reflections, estimate at w3u 7p elj, (dcf6iyiju,l bn; dml;-/phat angle(s) it is not possible to hear the whistle clearly on the playground outside the doorway.    $^{\circ}\,$ either side of the normal.

If parallel light falls on a single slit of wjb*g7x) ccscwg3 b.- :sdx az(idth D at a 30$^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain beetle y0j(ay da,w-5.m tx fnhave a series of parallel lines across them. When normally incident 460-nm ligyjnxta0f,5(ya w -. mdht 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 centimeter must a grating have if tg5hhvi5f7,rx 2 vtbp w(g8it8here is to be no second-order spectrum for any visibp(7h t8viibv xt,fhg52w8 5rgle wavelength?   $ lines/cm$

Show that the second- and third-order spectra of white light produc bxb2 cnu53m7qed by a diffraction253 nq7 cxbbum grating always overlap. What wavelengths overlap exactly?

  When yellow sodium light, 6squ 2j gb6wktz(x5 f+$\lambda\;=\;$ falls on a diffraction grating, its first-order peak on a screen 60.0 cm away falls 3.32 cm from the central peak. Another source produces a line 3.71 cm from the central peak. What is the wavelength of the new source? How many $lines/cm$ are on the grating?
   nm
  $ lines/cm$

  Light is incident on a diffraction grating with and the i7p)atm) holt 6f1 4nmpattern is viewed on a screent)ha1p it)nf m6 lom47 2.5 m from the grating. The incident light beam consists of two wavelengths, $\lambda_1\;=\; 4.6\times10^{ -7}\;m$ and $\lambda_2\;=\; 6.5\times10^{ -7}\;m$. Calculate the linear distance between the first-order bright fringes of these two wavelengths on the screen.    m

What is the index of refraction of a clear material if a minimum of 150r;frqptq8xw fhi (w e8 o82i47 nm thickness of it, when laid on glass, is needed to reduce reflection to nearly zero when light of 600 nm is incident normally upon it? Do you have48 rfq7iww2tihpr(fq 8ex ;8o a choice for an answer?

  Monochromatic light of variable wavelength is incident normally on a thf xg5n3 :mhf2,dgcxp 5in sheet of plastic film in air. The reflected light is a p g,x5nfd5hc 2mxf3:gminimum 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 5 8mjkn-ln q84kf6l4u( okpmq;l,zuwthickness needed for an anti-reflective coating $(n=1.38)$ applied to a glass lens in order to eliminate
(a) blue (450 nm),    nm
(b) red (700 nm) reflections for light at normal incidence.    nm

  What is the minimum (non-zero) thickness for the air layer between two fk hcqyn)2.89ka f;j0iwcbii( lat glass surfaces incfabi iwkqy;9 jh.0ck)(82 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 transmitteg,qw) a,z0w*lme(p5w /y orcrd through a thin film layered on a flat piece of glass. Draw a diagram, similar to Fig. 24–30 or 24–36, and describe the conditions required f0g)r (rqc,a ,m5l w/pwyzo*ewor 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 off a smod6 l -amdvag8wen;c)5oth lake is polarized mm-e l6c d5wa dnag8;v)ost strongly?    $^{\circ}\,$

  At what angle should the axes of two Polarg9 d*lj8 11mx oqawrs6oids be placed so as to reduce the intensity of the incident unpolarized li8x9w1 lramj1odsg *q6 ght 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 w0nsmaunk 7 gg;)e:we +hn99ctransmission axes are at right angles. A third polarizer is placed betwcg;wn 7ng :emke9+ a)h0u9nws een 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 successi jjb iorx(; unucvc(795z9-econ 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 ofkhjymt-h5 gfcn kz ;d4/0z.o. width 1.0 cm and is pointed at the Moon, which is approximately 380,000 km from the Earth. Assume the laser emtn4h/ dfy o;czzmg- .5k0.hkjits 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 p1 iuc q gsy/ge,;x3+seach 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 czrx:vr6y (ru-h+ 3j ebr;i t)$(n=1.34)$ 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 withnevtc sxsoou4p1 / .; ,rdfjs4ea d349 each other. They are located ata49d /sjf41 vno3 o r;u.s4p ecxds,et points $S_1$ and $S_2$, separated by a distance $d\;=\;175m$, Fig. 24–61. What are the first three points on the y axis where there will be destructive interference? (Destructive interference in this case means that a radio receiver placed at that point would pick up no signal).    m    m    m

  A parallel beam of light containqdkdcw::jknmotmg - 1()e 6q/ing two wavelengths, 420 nm and 650 nm, enters a silicate flint glass equj kcg - e:d6 dmnm/q1k)q(tow:ilateral 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 hh:cbi.7 6uo sj w7kur)as 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