Does Huygens’ principle apply to sound r*e+bo aiq18c zn wp k(;qq.;xwaves? To water waves? Explain.

What is the evidence that.fes ;umqf,) n light is energy?

Why is light sometimes described as rays and sometimes 6 3ik cndnwwt0-1gq6u54pao zas waves?

We can hear sounds around corners, but we cannot see around corners; yet qt euh/c (a;ljpdb 506both soundqda(h5jtul ; 6 cb/ep0 and light are waves. Explain the difference.

If Young’s double-slit experimew2rsamif86;bglipt549f 82thjgv ,e off7 0z nt were submerged in water, how would the fringe ihs8wvff pmg8 t47, b6o20 e5;9rzf iafjlg2tpattern be changed?

Monochromatic red light is incident on a double slit, and the in,g 6vlurp-7xdnwzdm1o:l6ga3 2 6pvoterference pattern is viewed on a screen some distance :-n dv luz vdg 626pmow6o g3a,71xprlaway. Explain 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 destructively interfere if their pathmes*/ubte; a;0w6 u we lengths differ by howu 0eube/w6se;tw;*ma much?

Why was the observation of the double-slit interference pattern more conp;hatapi u: x:z ++r2dvincing evidence f2 rzadpa i :t+;xh+u:por the wave theory of light than the observation of diffraction?

Compare a double-slit experiment for sound waves to that lhqn9cckam9e7gi2j1w 7vd.- for light waves. Discuss j-7 cak1ih9.wd 9vn c2e7qgmlthe similarities and differences.

Why doesn’t the light from the two headlights of a distant car produce an inkx-ct +bz9(iyterfcy-z9ibt kx+( erence pattern?

Suppose white light falls on the two slits of Fig. 24–7, but one slit9tlo9rlm tz 8v0/ q8:g)7gxoy; gcrf u is covered by a red filter (700 nm) and the other by a blue filter (450 nm). Describrtv;ml0g 8x7y8o/r 9:gl9t oqug f cz)e the pattern on the screen.

When white light passes thrvg x8f hii)xt o)g;(2c-c 6kzsough a flat piece of window glass, it is not broken down zgk8x 6vts)o i; ix 2-)c(cfghinto colors as it is by a prism. Explain.

For both converging and diverging lenses, discuss how theizeek h4 zfrl*k q,ukz*w /m.f7w6;1e focal length for red light differs from that .*er7e4iwm; h fzkzl* f61k/ueqwzk, for violet light.

A ray of light is refracted through three different mater1f80vhk f+svt6 ,i mpdials (Fig. 24–55). Rank the materials according to their index of refraction, leas6,vi stvk01dfm+pf 8 ht to greatest.

Hold one hand close to your eye and focus on a dd gz5j. vlm1kg- cw.*iistant light source through a narrow slit between two fingers.*.1i dlg 5. mzwjg-ckv (Adjust your fingers to obtain the best pattern.) Describe the pattern that you see.

What happens to the o8x *n sfe-r:+bryd* xdiffraction pattern of a single slit if the whole apparatus is ime sxo8dr x:-+* *fbynrmersed in (a) water, (b) a vacuum, instead of in air.

For diffraction by a single slit/gvk w.yxm2+u , what is the effect of increasing (a) the slit width, and (b) the wavel uwx.2gmvk+y /ength?

What is the difference iw0.3a kmrtd n*t )sjx z xim**h n:jat/)i(p/mn the interference patterns 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 sljuex:velp ,/ gqypy u 0*5ds5 d,,nhl7its, (b) closely spaced slits?5x, nh:se, pp0ly/7*,dv5ylu qduej g

White light strikes (a) a diffraction gratingbl2l x0 h t8il*ogh*e6, and (b) a prism. A rainbow appears on a wall just below the direction of the horizontal incident beam in each case. What is the color of the top of the rainbow in eacg2x06*o8 i lhtbell*hh case? Explain.

For light consisting of wavelengths between 4ub*j;tqph 5 r200 nm and 700 nm, incident normally on a diffraction2hbjp*qu ;5 tr grating, for what orders (if any) would there be overlap in the observed spectrum? Does your answer depend on the slit spacing?

Why are interference fringe fkol)px5ne.g2gb m m h7(;,los noticeable only for a thin film like a soap bubble and ng2ego(l n7;xm )phm .,l kf5boot for a thick piece of glass, say?

When a compact disk (CD) is held at an angle in whisqy47sws 9za wapl z/p7*t+r*te light, the reflected light is a full spectru w azspa /yw+z9qsl**4t7ps7 rm (Fig. 24–56). Explain. What would you expect to see if monochromatic light was used?

Why are Newton’s rings (Fig. 24–31) kp*6lkgm+ 4 i(c)ye/z/n9uc6s ouiwwcloser together farther from the center?

Some coated lenses appear greenish yellow whenmzt;hr / xfwbri19y0b.. c+bu seen by reflected light. What wavelengths do you suppose the coat9 +0 bubh.x./yc1fmr ziwr;bting is designed to transmit completely?

A drop of oil on a pond appears bright at its edges, where its tdvebs ,p0* ) )njymxp+hickness is much less than the wavel0, *)j) mspdvxbnep +yengths of visible light. What can you say about the index of refraction of the oil?

What does polarization tell us about the nature;9jyfl, v3y2 sszro -j of light?

Explain the advantage of polarized sunglasses o+ 7hm )4 bf9nwwofyry1i i;ky.ver normal tinted sunglasses.

How can you tell if a pair of sunglasses is p pn 9/gp+7bpa8g0hua polarizing or not?

Two polarized sheets rotated at an anut2mv 7iok/-9.k joupgle 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;rb g,icx0 5:p + gak5ceb3zi97 mgsdz atmosphere?

If the Earth’s atmosphere were 50 times denser than it is,f mi/hx7ik 5md9u9pq 0 would sunlight still be white, or would it be some other colorkhxqi 5pf m90uim d/97?

  Monochromatic light falling on two slits 0.016 mm apart produces th,4uzhzcn :y3o :ohhgxc;r4 b6e fifth-order fringe a ::uynh,3xhc orzbocz46;4gh t 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 observed at an angle of 19f/kmd zgn4nge b4n :j71wy2oxg 3s 0e8$^{\circ}\,$ when the light falls on two narrow slits. How far apart are the slits?    $\mu m$

  Monochromatic light falls on tyrv ud-6nup1 8wo very narrow slits 0.048 mm apart. Successive fringes on a screen 5.00 m away are 6.5 cm apart near the center of the pattern. Determinu8 d1uvn-py6r e the wavelength and frequency of the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of light from a He- sx/kf ne9 48kzefptaa52qy ;*vb1l .gNe laser, with a wavelength 656 nm, falls on two very narrow slits 0.060 mm a59 ekae1q4 ; *a f2l/fsygp nt8vb.kzxpart. 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 fa lniw912d ngx8lls on two slits 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 is812 9gi xdnnwl the separation of the two slits?    mm

  If 720-nm and 660-nm light passes thmp9 mz5ekgf+0jqr x ;)rough two slits 0.58 mm apart, how far apart are the second-order fringes for these two wavelengths on a screen 0xr)mj5zeg+q km;fp91.0 m away?    mm

  In a double-slit experiment, it is found that blue li;6c;ec f0 dbpeght of wavelength 460 nm gives a second-order maximum at a certain location on the screen. What wavelength of visible light wo bc e;dc60fe;puld have a minimum at the same location?    nm

Water waves having parallel crests 2.5 cm apart pass thrfq72so7;kiz wough two openings 5.0 cm apart in a board. At a point 2.0 m beyond the board, at what angle relative to tq2siw;7 kzfo 7he “straight-through” direction would there be little or no wave action?

Suppose a thin piece of glass is placed in front of the lower slit in Fig. 24–jz 2eytd(ldy**( xbn n6hdv ++7 so that the two waves enter the slitzvd2(tn 6 b+yel+dj(dnh *y*xs 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 thi z gsq*3ixk)f r-:f+pvrd-order maximum for light of wavelength 500 nm is located 12 mm from the central bright spot k+pr*3svigx qfz : f-)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 light. Findp9(mm)lx .i jexed1 z8 the distance between adjacent bright fringes on a scre9xmx)(.dme 8zl iej1pen 5.0 m from the slits.    mm

  Light of wavelength 480 np,mcy)-::o ywres0) -a6xztsr6qpffm in air falls on two slits $6.00 \times10^{-2 }\;mm$ apart. The slits are immersed in water, as is a viewing screen 40.0 cm away. How far apart are the fringes on the screen?    mm

  A very thin sheet of plastic (n=1.60) covers one slit 9np;r qeqj..h of a double-slit apparatus illuminated by 640-nm light. The crqe9h.;jpn. q enter point on the screen, instead of being a maximum, is dark. What is the (minimum) thickness of the plastic?    nm

  By what percent, approximaa.(y4b/ 1yyo j j)iotk: 90qwqzgi(ottely, does the speed of red light (700 nm) exceed that of vio atyowty(y /:j1.k4 iojg )09q(oizqb let light (400 nm) in silicate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece of9 pxrw/92auz q 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 waj: eosrt.ahn-u)1k(n j4jxsig 0 :)mic/exg5velengths, $\lambda_1\;=\;450\;nm$ 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 angularjg1q hv;s(wx.*om d e4 width of the c. egh j1*4 ;wovm(qdsxentral diffraction peak?    $^{\circ}\,$

  Monochromatic light falls on a547f af1;z1 twbysxoi 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 n:+ukww3d :- yt6ejo xpm falls on a slit that is $ 3.20\times10^{ -3}\;mm$ wide. Estimate how far the first brightish diffraction fringe is from the strong central maximum if the screen is 10.0 m away.    m

  A single slit 1.0 mm wide is illuminated by 450-nm h(psxl:8s11 ue, ci:kml zz4i* egab: light. What is the width of the central maximum (in cm) in the diffraction 4::bm*pi(u ,z1assl:xee8i1cz klgh pattern on a screen 5.0 m away?    cm

  Monochromatic light of wpfn0p8 thm s73avelength 653 nm falls on a slit. If the angle between the fir7t30mpn p8 fshst bright fringes on either 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 ft65 qj) )jatetm);hc2ibh )o m behind a 0.0348-mm-wijc at)mhi)j ;btfq6)2 )eh ot5de slit illuminated by 589-nm light?    cm

  When blue light of wavelength 440 nm falls o glhc vzp;/*znsb* 4ho:g ys*.n a single slit, the first dark bands on either side of center ag:yl szzs nhc;*.o *4v*gpb/ hre 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 crn so(x sy)1(;+fmxwn geates a central diffraction peak that is 9.20 cm wide on a screen that is(w()sogmx1+ xfs ny;n 2.55 m away. How wide is the slit?    mm

  If a slit diffracts 650-;;6yj/s7 ov f6hu7r bbkkf-mv*: yku znm light so that the diffraction maximum is 4.0 cm wide on a screen 1.50 m away, what will be the width of the diffraction maximum fo-*z u7bmky6f;:f 67vkrhj/bo yv; kusr light of wavelength 420 nm?    cm

For a given wavelengtflp5d hl-l; hzgf(us*zcv o76z :g43 kh $\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm li3 -(,thzfo lfrght produce a second-order maximum when falling on a grating whose slift, f3-(rzl ohts 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 centim , ga/wlz3qkb)eter does a grating have if the third-order occurs at an 18.0kgw zl,b3)/qa $^{\circ}\,$ 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 , 2rk3rml:i 3 geh(s3r lpglm;light falling on a diffraction grating is observed at a 15.krs mgr3ll ;h(er :3m 3,pi2gl5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction grating has k (7y ikn,ukpm gi0+;u$ 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 o y3u*aigf iket5qesn ( .219fon 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 spectr 3b.84pjfd5i fcu npprq;7m 2posu q059m+qat al order that can be seen if a grating with 6000 lines per cm is illuminated with 633-nm laser light? Assume npupqp85 c7qtd qn5imf3.u; r9p b0+j2aos4fmormal incidence.   

  Two (and only two) full spectral or4y e j6s0gopx-ders can be seen on either side of the central maximum when white light is sent through a diffraction grating. What is the maximum number ofjexp6g40yos - lines per cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containing 1-uf/s 8uwhhg; or4akwavelengths from 410 nm to 750 nm falls on a grating with okr4s- hhuuf1 ;8wg /a$8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which produces monochromaticzy0)n yp(uw);p3t3 sosa( r rx 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 a (e 8p,bpvkedyj4c l;zr f;g2,df ;;ml$9500-line/cm$ 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 mosp kd9 ,x*p8mqdt strongly reflected at the ce p*xdd8pqkm, 9nter of the outer surface when illuminated normally by white light? Assume that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are thenfxdr9u * edg s,99axo6.pg-u dark fringes in Example 24–8 if the glass plates are each nd.69fe d us-u9ar*gx,p9x o g26.5 cm long?    cm

  What is the smallest thickness of a soh:6if5qmtcp 7yif ( c7ap 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 y0zq,r+dp sk v e*t tla7:hph./ellow ($\lambda\;=\;570\;mm$ 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 spot at 1xsl)dd(ilw +9d* k0g f or,agthe center) are observed when 550-nm light falls normally on a planoconvex lens resting on a ifw*r)9a+0d l(g 1olxkds ,gdflat glass surface (Fig. 24–31). How much thicker is the center than the edges?    $\mu m$

  A fine metal foil separates one end of twodo49d-vth2n l3qlkhy/* p r -q pieces of optically flat glass, as in Fig. 24–33. When light of wavelength 670 nm is incident normally, 28 dark lines are observed (with one adpdorn2y-h l3lt 9 qq*-4hv/k t each end). How thick is the foil?    $\mu m$

  How thick (minimum) should the air layer be between two flat glass surf.jh1ci g/+2 sxjywqs 7aces if the glass is to appear bright when 450-nm light is incideng1 2wh +sc7xij/q yjs.t normally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, suspectew )mka-f1n) to20uew bd of being 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 alcoholpq wm :rq t:szk,;hf*g42ja o1::ncsh $(n=1.36)$ 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 i91o :rm5lnr) /npwxsi(jh 7r mn a liquid, the diameter of the eighth dark ring decreases from 2.92 )rxr5nmi 7ornj w p( s:/hm1l9cm to 2.48 cm. What is the refractive index of the liquid?   

  What is the waveleng9o omme 7*hiutqv ,c+)df :hh)th of the light entering an interferometer if 644 bright fringes arihfuo+dt7)vo9 :)m h,*hq cmee counted when the movable mirror moves 0.225 mm?    nm

  A micrometer is connected to the movable mirror of an interferometer. When the*ynwp(q v* y.(pviuc; uqbn1g-- c5n d micrometer is t*p1y 5dbc; (-nq yi*n. pugcn-vv(uqwightened 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 mir7 *md .8 4y;lyy6eqqg9rsyrsrror $M_1$ 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. qjqw3tkc.gfg 9 bg3+124–59) 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 a reference line. The light used has a wavelength of 610 nm. Caj3+cq twfg9g .g1qb3k lculate the index of refraction of the gas, assuming that the interferometer is in vacuum. $n_{gas}$

  

  Two polarizers are oriente (4 )5uyz-u7 gniprmzwsoqc /6d 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 h1q : szz 6x46zag0azgair–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submerged in water fj q /;mo+ zoqh2ocia-vn530wif the light is hitting the fo-wj0cahm qo2 i5 nv;/zoq3+diamond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so thatc1wr,z7 tus1d the light passing through them is a maximum. At what angle should one of them be placed so that the intensity is subsequently reduced by hawducz ,t17s 1rlf?    $^{\circ}\,$

  At what angle should the axes of two Polaroids buu)kxlk3p, 6( (qeh1 s lqlz5 nq6xf(ae placed so as to reduce the intensity of thqaz)h kl,qe63l(fu l u1nxsk px65(q(e incident unpolarized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are or2-fk w7u;qidzr2:lfr g+wc)gsj 0 ot+iented 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 38.lb 91y )7e2tg(ukl o-okgkb 7d0$^{\circ}\,$ 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 wategq(ou 4)l/x ryr for light coming from beneath the surface? Compare to the angle for total internal reflection, and to Brewster’s angle from above the surface.lo(q gy)rx /4u
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 sh vfp0 (9jmfbnbo)d8lcac92 x8eets, each of whose axis makes a 45 lc d m8(bpc09j bf9axov8n)2f$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength g8yhhw p+b5; bi,6uw nj 23gvg$ 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 airplanrt )fr fk-r4u73(xzrdes can interfere with the direct signal from the 3 4r 7f)rzx-r(ku rtdfstation.
(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 througjz*tt 2r)ycg( h a diffraction grating with trt2gy()*z jc$ 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 s4belgdn1i3* 75pkuqwe ( 3kvycreen 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 is the wav1ek 5y3pq eg7n3 idwu4 *kl(bvelength of the unknown light? $\lambda_2$    nm

A radio station operating atnk;3j*h7zkv5 ( a 52pgehhqca 102.1 MHz broadcasts from two identical antennae at the same elevation b kp5; c(2 5kh3 gh7qheanzja*vut 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 backh fj1wb3zd1 i;,y.hok from an 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 whish 1zydojkiw;3h .b1, ftle clearly on the playground outside the doorway.    $^{\circ}\,$ either side of the normal.

If parallel light falls on a single slit of widt :,u*o,nowmph h D at a 30$^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain beetle have a serim45tqv4)b fu,7b dp j1y d1qbnes of parallel lines across them. When normally incident 460-nm light is reflected from the wing, the wing a4qpum d75d n j1b)vbf,yb q4t1ppears 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 be no sg ;t,igz 5a.mfecond-order. zf;5 ami,gtg spectrum for any visible wavelength?   $ lines/cm$

Show that the second- and third-order spectra of white light produced by rjkkx8d3+ b9l a diffraction grating always overlap. What wavelengths overlap exactly3 +9rkjkbd 8xl?

  When yellow sodium li c ,x,zze6seji /-+jbaght, $\lambda\;=\;$ 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.9 0hr9; nmezp) yrnyv grating with and the pattern is viewed on a screen 2.5 m from the grating. The p0ym9ynreh .vzn9)r ; 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 ifcqm+fex0jp5o+k g3l 9 a minimum of 150 nm thickness of it, when laid on glass, is needed to reduce reflection to nea oqp j3fe5gx0c+9mlk+rly zero when light of 600 nm is incident normally upon it? Do you have a choice for an answer?

  Monochromatic light o7 ,+:lrvuqbb+gtie 6df variable wavelength is incident normally on a thin sheet of plastic film in air. The reflected light is a iu ,e+v 6tlrq:+b7bdgminimum 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-reflectiveju6c/w kst : hlvk-(5fc(dzos yk31 8c 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 thec6g2kyq , vl l3j:zno3 air layer between two flat glass surfaces if the glass is to ap6nllq cj3 o:yz, 3k2gvpear dark 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 th::oxjhsn eqe,.2t fc 7in film layered on a flat piece of glass. Draw a fo.ehtc 2:n ,esxq7:j diagram, similar to Fig. 24–30 or 24–36, and describe the conditions required for maxima and minima. Consider all possible values of index of refraction. Discuss the relative size of the minima compared to the maxima and to zero.
24-30
24-36

  At what angle above the horizon / y xy((m+zqzjfkmyszx 65f/4 is the Sun when light reflecting off a smooth lake is y s/z mxzyq6zyjxk(fm+(f5/4polarized most strongly?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be:;*wl 9qf50 ytnf7asm:vtq s5hm-wza placed so as to reduce the intensity of the incident unpolarizel:5* ts5z:mw70mt qa-; fsqywa9 hvn fd 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 falls on two polarizer sheets wx)3 twe:cool:,4s5x,he my upd kk*9r hose transmission axes are at right angles. Awm os 4lchyr*,9o:3, :p dukx)xet5ke third polarizer is placed between the first two so that its axis makes a 62$^{\circ}\,$ angle with the axis of the first polarizer.
(a) What fraction of the incident light intensity is transmitted?    $I_0$
(b) What if the third polarizer is in front of the other two?

Four polarizers are placed in succession with their axes vertical, at ehfb i6fe0) khlri+,2t brir;y2b/8s 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 the Moon,ev lu*st,i7q q*rs8p1 which is approximately 380,000 km from the Earth. Assume the laser emits waves o1lepr ,**stu q87ivqs f 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 placed at a- oqirvcl7-(h 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 pchro3gi8r39 nw5vy5 7tr9s4k 7ydi o$(n=1.34)$ 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 antennasunmdq, kmh 9( 60c(,xyv8wgqm radiating 6.0-MHz radio waves in phase with each other. They are located at pointq (8h9wmx(umvmc 6dyn 0 g,k,qs $S_1$ and $S_2$, separated by a distance $d\;=\;175m$, Fig. 24–61. What are the first three points on the y axis where there will be destructive interference? (Destructive interference in this case means that a radio receiver placed at that point would pick up no signal).    m    m    m

  A parallel beam of light containing two wavelengths, 420o 4sqtcv/b/kcb7 rc7) v 6us5g nm and 650 nm, enters a silicate flin/ ccusqs t gvc)o6b54/rv7k 7bt 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 h4ms8)cyqoyawu t8w5.2ym9 vlens 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