Does Huygens’ principle apply to/h vsq 6at(8dflqs3bg: ca-4b sound waves? To water waves? Explain.

What is the evidence tloy9b ft8bt 0+i:m/cthat light is energy?

Why is light sometimes described au p 0(s9dkld-pbz, 1rzpd,qx/s rays and sometimes as waves?

We can hear sounds around corners, but we cannot see around corners; yet bo 0m85 kvw(dtc;un qb d4vz1)ixth soundzwxc d(8m)dnu1q5t4 ;kvvib0 and light are waves. Explain the difference.

If Young’s double-slit experiment were submerged in water, how would thq: w g;n4gvcu4e fringe pattern be chan4:;ucvnqwg4 gged?

Monochromatic red light is incident on a do4a9/8icih- xjdnk 0 lr/uf.zsuble slit, and the interference pattern is viewed on a screen some distance away. Explain how the fringe pattern wouiij 0 f.k hz-/8acurdx/49s nlld change if the red light source is replaced by a blue light source.

Two rays of light from the same soht;:/w u.e( h bhznw oi7l09ppurce destructively interfere if their path lengths differ7/w ohz9.n 0l;i( :whpbptehu by how much?

Why was the observation of the double-slit interference pattern more convinpwak/hyq-3 3 ofo.h-bq1 f4iycing evidence for the wave theow13fh.qiq-kpoyf3/bah y 4-ory of light than the observation of diffraction?

Compare a double-slit experimen/y+tq1c,wua+ h,+vkzv z e)ptt for sound waves to that for light waves. Discuss the simila +)aqpzky,v tevcwt+ /,uz1h+rities and differences.

Why doesn’t the light from the two headliiw z)96 .qs xjm2ni70xhiaodn 3 sz4u6ghts of a distant car produce an interfereo ) zu4q9zw3aids. nisi7m0nh2x66xj nce pattern?

Suppose white light falls on the two slits of Fig. 24–7, but one slit ie + y)x.krte8avbgv7 8s covered by a red filter (700 nm) and the other by a .8yv+7egak8t xr ebv )blue filter (450 nm). Describe the pattern on the screen.

When white light passes through a flat piece of wind x8d/4 0sjwik2eim*l low glass, it is not broken down into colors as it is by a prism. Eld k j*w2i4m/ 8exil0sxplain.

For both converging and diverging lenses, discuss how the focal lenmnq1ci101q ca gth for red light differs from that for v1 aimq1q c10nciolet light.

A ray of light is refracted through ttyu6a39nsj-+1xg1yu.dwy)xq0 mvdr hree different materials (Fig. 24–55). Rank the materials according to their ind6 1ta j9 +s3ddv 1-qgn yur)uym.xwx0yex of refraction, least to greatest.

Hold one hand close to your eye and focus on a distchz i/cj7av6 d00g qk7ant light source through a narrow slit between two fingers. (Adjust yoz6q/0hv7icadkc07 gj ur fingers to obtain the best pattern.) Describe the pattern that you see.

What happens to the diffraction pattern of a single slit -j 63mesi rqark7ssm)2ud(m6 if the whole apparatus is immm )3ju7 m2karss6ds i6( q-emrersed in (a) water, (b) a vacuum, instead of in air.

For diffraction by a single slit, what i.och+ aevs-n*bdo.y0 y o6qf2xogx29s the effect of increasing (a) the slit width, and (b) the waveleng .2v yohd onbe* xy-gqfsa9+o6cx2o.0th?

What is the difference in the interference patterns formed (a) by two slir dujq-1x5n6dts $^{-4}\;cm^2$ apart, (b) by a diffraction grating containing $10^4lines/cm$?

For a diffraction grating, what is the advantage of (a) many3ilj1rx:p 6o 7wotp15zo8ll x* i gtx) slits, (b) closely spaced slits?t gjpll1 i*6tpwz:rx3i7ox18 oox l)5

White light strikes 8x6zh)g 8+mgxlf45 0q xqf ijl(a) a diffraction grating, and (b) a prism. A rainbow appearsl468 gmf0xjizq lx q8+g5h)f x 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 x( +ruqcca(-iw( w5g v400 nm and 700 nm, incident normally on a diffraction grating, for what orders((x q+w ca5icu r(-wvg (if any) would there be overlap in the observed spectrum? Does your answer depend on the slit spacing?

Why are interference fringes noticeable only for a thin film like a soap bubblw9xk,d,rf)o2 hdm r5 me and not for a thick piece of glass, 2 9kx)ohrd,w dmr m,5fsay?

When a compact disk (CD) +vfeq6y)r wozr26yp: is held at an angle in white light, the reflected light is a fuy2:z6w 6+)pe oqyr vrfll spectrum (Fig. 24–56). Explain. What would you expect to see if monochromatic light was used?

Why are Newton’s rings (Fig. 24–31) closer--wwrxaktr 7uv; -9fey5m fu1 together farther from the center?

Some coated lenses appear greenish yellow whix ccl46kk9ia9 7i3nhen seen by reflected light. What wavelengths do you suppose the coating is designed to k46i97n x3 cilhaick9transmit completely?

A drop of oil on a pond appears bright at its edges, where itsoeecjl a:5+p. thickness is much less than the wavelengths of visible lile5aoc+ ejp .:ght. What can you say about the index of refraction of the oil?

What does polarization telnk)fzh;frl *qd;9 h/el us about the nature of light?

Explain the advantage of polarized sunglasses over normal tintedfk1 6 cvtf zqei3bqvj0jl/(6- sunglasses.

How can you tell if a pair of sunglasses is polariziekx :8s/vnv; fuc)s)cng or not?

Two polarized sheets rotated at an z/hdc+,fpf4gangle 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 atmos v//wf - zp*;esmot-ddphere?

If the Earth’s atmosphere were 50 timez6gnmdg (//c wpu+m d)s denser than it is, would sunlight still be white, or would+ d z6cm)w(/gudp n/mg it be some other color?

  Monochromatic light fallq7agr73qnzmc+n y5 m /ing on two slits 0.016 mm apart produces the fifth-order friyn c+ qgm3 5rqz7n7m/ange 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 observed j o9p1px 7e2pmat 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 mm apart. Successive f8) xt/nids iz e*e1j6aringes on a screen 5.00 sez18)jii adnxe *6t/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 fr88 ij 8iitchjshjt z:9i239yyom a He-Ne laser, with a wavelength 656 nm, falls on two very narrow slits 0.060 mm apart. How far apart 9 :i sh2 8yic38thjtyjij98z iare 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 an int j2m*w (id,u7 t34a*o qzciokserference pattern in which the fourth-order fringe is 38 mm from iwa*7tc iudks4q*om(3, z2jo 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 throughn4dhdd*ly ;c8 two slits 0.58 mm apart, how far apart are the second-c ;ydld 84ndh*order fringes for these two wavelengths on a screen 1.0 m away?    mm

  In a double-slit experiment, it is found that blue .27wippbv 9fb light of wavelength 460 nm gives a second-order maximum at a certain locativp fwb97 .p2ibon 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 tw* j p*nd/6 j 8gms8gcyizq9z,go openings 5.0 cm apart in a board. At a point 2.0 m beyon g9jz8c ,8*my6nqdp * /zigjgsd 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 isyuowac8r 5lj6p-bgw u:5qnz .yi)95ga i-iz ) placed in front of the lower slit in Fig. 24–7 so that the two waves enter the suig.py 8zw)q z-r5-j5) 6c 5ig n:wiaoua yl9blits 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 thirdp0qrb9wb 0j e.wy36e a +e+rko-order maximum for light of wavelength 500 nm is located 12 mm from the central bright spot on a screen 1.6 m from the slits. Light of wavelength 650 nm is then projected through the same slits. How far from the central bright spotw+o qyke+0 .a 0e93jwbp rreb6 will the second-order maximum of this light be located?    mm

  Two narrow slits separated by 1.0 mm are illuminated by 5444 .0pw-kszum oa,i/iym sb( h. nm light. Find the distance between adjacent bright fringes on a screen 5.0 m from the slitym./oik(4.a- sp, bu s mi0zhws.    mm

  Light of wavelength 480 nm in air falls on two slb v d;asl t:og +b;tkr-9xz qypdmiv13/9*u-jits $6.00 \times10^{-2 }\;mm$ 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 9 q. yr.0qgipldouble-slit apparatus illuminated by 640-nm light. The cenqy.l0 r9. igqpter point on the screen, instead of being a maximum, is dark. What is the (minimum) thickness of the plastic?    nm

  By what percent, approximately,urky;,if +l; f*hz bt( does the speed of red light (700 nm) exceed that of v zi uhlb;,;(*+r fktfyiolet light (400 nm) in silicate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece of glass at a 60.0b;j ncnzex ah 7/3t;;f0$^{\circ}\,$ 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 conta/q0fu rr;x3pacl. 3o ) wrzl5hining 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 onlx9j7wqp*s s( gn0 oi4 a slit 0.0440 mm wide, what is the full angular width of the centra9wss7j l pin4o* q(x0gl diffraction peak?    $^{\circ}\,$

  Monochromatic light falls on wanhw lntd t/7pj41kt 6(9dx(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 falls8.lrzi dp;fmtc /oe -h..zb*n 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 illum+6axt xjm)ccnf +:5 fsinated by 450-nm light. What is the width of the central maximum (in cm) in the diffractionfm6ft x+) :ccn+asj 5x pattern on a screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm falls on a slit. If the jz i9q/esx2 g59w bu9pangle between th2wex sui9j p9/z 9b5qge first bright fringes on either side of the central maximum is 32$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central d (moxuct2 svr* g*4-fxiffraction peak on a screen 2.30 m behind a 0.0348-mm-w u(g 42*otxs*mfvrc-x ide slit illuminated by 589-nm light?    cm

  When blue light of wavelength 440 nm falls on a single slit, the first dark bakv(e 4c:jjf8 (4qu juznds on either side of center are separated byc u j8k u4zqe(fjv:j(4 55.0$^{\circ}\,$. Determine the width of the slit.    $ \times10^{-7 }\;m$

  When violet light of wavelength 415 nm falls iwt6 af+*w mqbn -si6;on a single slit, it creates a central diffraction peak that is 9.20 cm wide on a screen that is 2.55 m away. How wi mf6n*i;bwqwti6 a-+sde is the slit?    mm

  If a slit diffracts 650-nm light so that q6+wnsac1nc /5f)b l 8,ugprc the diffraction maximum is 4.0 cm wide onqc5,g /6bcfr p)u sawnc n1+l8 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 wavelength d,rd st+ ps,d0$\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm light produce a second-order maximum when falt/,xku5u s*0fg7z np uling on a grating whose sli 7pktsnx u,ufgu0z/5*ts 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 txwbmk1 rou :nq +2t5/bhe third-order occurs at an 18q: unoxt5/1rm b+wk2 b.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- .x5raf: 5sj h0,yizjfnm light falling on a diffraction grating is observedaj0,xfirhz.f: y s55 j at a 15.5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction gratinym ).z9wwz iyi 3omnaj68h6mr 5 a+o;og 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 normalllk 9k6zrpvajc1 g;(l; 1djb.my on 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 spec i8;,pr4ox) 0;eqz 9oic mduwwtral order that can be seen if a grating with 6000 lines per cm is illuminated with 633-nm laser li, 9;dq uwx; w)c irm0zo8o4epight? Assume normal incidence.   

  Two (and only two) full spectral orders can be seen o5uaaa ;w 9vc.2b8r7-o .0mvzyydimyh n either side of the central maximum when white light is sent through a diffraction grating. What is the maximuv yw b-.zmim;98a2 c hvoru0aa .5dy7ym number of lines per cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containing wavelengths haja ,9 2)c/sknd2nyy from 410 nm to 750 nm falls on a grating with 22kc/nd, syhay )jna9 $8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which produces monochromatic light ofjvt2v5p/ lwlq cpfl)8z-0k1 qp-z yu) 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 line7: x9iwwus,4phf9zz gs are measured by a $9500-line/cm$ spectroscope at angles, on each side of center, of +26$^{\circ}\,$ 38$^\prime$,+41$^{\circ}\,$ 08$^\prime$ and -26$^{\circ}\,$48$^\prime$,-41$^{\circ}\,$ 19$^\prime$. What are the wavelengths?
$\lambda_{26.72^{\circ}}\;=\;$    nm
$\lambda_{41.23^{\circ}}\;=\;$    nm

  If a soap bubble is 120 nm thickwmh/;vf e6mg3-f3 iyf, what wavelength is most strongly reflected at the center of the outer surface when illuminated normallfgv3 i3/em- hwff6;y my by white light? Assume that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the dark fringes in Exampl2evb-yaa- j 7tzvyb/ 3e 24–8 if the glass plates are each 26.5 cm long?-bv 7zj2yaye- b3 av/t    cm

  What is the smallest thi- (l uid,g-kma22mmmm ckness 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 y7yldyi4-7da8exk.+ xqf.uzl 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 sc 0 pug-+6on1nt eh aacv7h--l2gpf*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 6h2saepl+pcfggc- v- h nnu1 t0o*a7- the edges?    $\mu m$

  A fine metal foil separ2c4xutb,x3ymd 3 kd;, +iwmb xates one end of two pieces of optically flat glass, as in Fig. 24–33. When light of wavelength 670 nm is incid;m ,,xdwkyxcxb3bid m32t+ 4 uent normally, 28 dark lines are observed (with one at each end). How thick is the foil?    $\mu m$

  How thick (minimum) should the air lahca;pet :6p p3 *nj6gnyer be between two flat glass surfaces if thpaepn* g6t :np;36 hcje glass is to appear bright when 450-nm light is incident normally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, suspected of beinfsa8wz wz ;dqtd8/ pj4jc(.b9g 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 alcoho; 3tl9hgwvvx6 l $(n=1.36)$ 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 ilvnnpygw1 / 60mmersed in a liquid, the diameter of the eighth dark ring decreases from 2.92 cm to 2.48 cm. What is the refracpy w/ngvln06 1tive index of the liquid?   

  What is the wavelength of the light entering an interferometer if 644 bright uim:e55ogxm)a h8aucts 9x -1fringes are counted when the movable mirror moves 0.225 mhe1a ucu g)-95ao :mxxst5m8i m?    nm

  A micrometer is connected to the movable mirror of an interfesr2 dkfwelli +;+(c9hwi r .vdg+ 7w9yrometer. When the microh;vi l w rdcy+dws9gw+.r2kie7f9+(l meter 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 mirrorc00odnl 0/ ti9zmgz+r $M_1$ 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 interfuzd- nz-mm /w1erometer (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 of 236 dark frinz mu1dn/-zwm-ges 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 oriented at m 3w0ks1j2(w)dpxc z eqk7a 8g65$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s angle for an)9 * iyzew3yzw air–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle ais2 c+ld*su)hnp 4 b-for a diamond submerged in water if the light is hitting-sih)+l2ad4 n u *bcps the diamond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the light passing through them is a ma+2 i*oy.gu xafximum. At what angle should one of them be placed so that the intensity is subse o+.yi* f2xugaquently reduced by half?    $^{\circ}\,$

  At what angle should the axes of two Polagyq 0 /-sz/ypg8w0os oroids be placed so as to reduce the intensity of the incident unpolarize0 w8g /y/ 0ss-ooqpyzgd light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are oriebt0t e (wa*0wbfz a22dnted 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 orientn k bv0-v1es 8ff01iwzed 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 reflectiospz rh3i5s/u (ns off the surface of water for light coming from beneath the surface? Compare to the angle for totp5/uhi3s ( rzsal 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 successive Polaroid sheets, eachs c4dmg3dh 6g;ty 4gt( of whose g d(6gmt3;dty4 g4shc axis makes a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength mq/ nm;t9ex5f$ 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 airplanesov*4qhqx3j w2: 9 qgn/p)f7oxzj( wxh can interfere with the direct signal fromw) 3v9 nh qhf4zq7(jo/x2q* : gxojxwp 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 sou; m)qv(.fa0mjcr4z 9nhe ujf) rces passes through a diffraction grating with j;m fuj 9r)f(vmz0 cqh. n)ae4$ 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 r/ssli .jt5dmo0/ gq 7apart. The screen istr ss5m.lj0o/q dg7/i 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 wavelength of the unknown light? $\lambda_2$    nm

A radio station operating at 102.1 MHz brl7bo u83f*jaboadcasts from two identical antennae at the same elevation but separated by an 8.0-m ho*3bo 78julaf brizontal 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 wida8h 2a,vlkls)e, and blows a whistle of frequenvkl,s)l28h aa cy 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 falls on a single ssc* 0resrex)a y 3fe,6n 8jf(ilit of width D at a 30$^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain beetle have a series of parallel l e c,0vc uo+q jsc(,nus1wk+-: ,4k-mpg aclmlines across them. When normally incident 460-nm light is reflected from the wing, the wing appears bright wh,cgk 4el0jqlw-os (k- cum npc1scv , ,u++ma:en viewed at an angle of 51$^{\circ}\,$. How far apart are the lines?    nm

  How many lines per centimeter must a 41dlj7a4o ,f8e 6+gup xlqlywxkp,-i grating have if there is to be no second-order spxd,g ,fpplo4ix wkel1 8 y47 jla-+6quectrum for any visible wavelength?   $ lines/cm$

Show that the second- k,jg5 xch,a0 eand third-order spectra of white light produced by a diffraction grating alwac age0hxjk5, ,ys overlap. What wavelengths overlap exactly?

  When yellow sodium ligh; 7ajmc0wcq) it, $\lambda\;=\;$ 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 withayl) :r27zxpz6 a(wgd e:fo;t and the pattern is viewed on a screen 2.5 m from the grating. The incident light b)za7ea d:fltg2o wp:y(xz;r 6 eam 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 refruo6 cje;b t (:qpvaz.j .:qi(vaction of a clear material if a minimum of 150 nm thickness of it, when laid z:a(vj (.6c;tbie. :jqvqo puon 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 a 7:y: ,aojriavariable wavelength is incident normally on a thin sheet of plastic film in air. The reflected light i:aai oy:, jar7s 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-reflective -c3zjg;i uy na3.n) q:pgjga,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) thics98n1a ftftvpa6 nw o1.lqc71kness for the air layer between two flat glass surfaq1ftlpt7.s1 wno9a6 nv c8f1 aces 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 transmitted through a t;z+4o m 8fx79z cv9tfooy:12sor zcdyhin film layered on a flat piece of glass. Draw a diagram, sic zm ofrf49s +yot8v92d;1zoxo7yzc:milar 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 horizhu((djh1yj-)ypu7k p9cw: yw-s o(wq on is the Sun when light reflecting off a smooth lake is polarized most strongly?hhj9wqk odw(pypu(j :) -wc(uy ys7 1-    $^{\circ}\,$

  At what angle should the axes of49c+po)nrnlw8ai.5 t) cw aks vgq78 a two Polaroids be placed so as to reduce the intensity 97c)apq 8n5wi k ag+n8a lw )t4.rcvsoof the incident unpolarized 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 whose trajgn9j z/ s g*uy 2fj.ienbg,)0nsmission axes are at right angles. A third polarizer is placed between the first two so that its axis makes a 60*g n /)sif9gyj,nz2j eub.jg2$^{\circ}\,$ 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 wi8rgo 9oi23 fi6rw pl.ith their axes vertical, at 30$^{\circ}\,$ to the vertical, at 60$^{\circ}\,$ to the vertical, and at 90° to the vertical.
(a) Calculate what fraction of the incident unpolarized light is transmitted by the four polarizers.
(b) Can the transmitted light be decreased by removing one of the polarizers? If so, which one?
(c) Can the transmitted light intensity be extinguished by removing polarizers? If so, which one(s)?

  A laser beam passes through a slit of width 1.0 cm and is pointed at the Mx6u sfv+s54 beoon, which is approximately 380,000 km from the Earth. Assume the laser emits waves of wavelength 630 nm (the red light of a He-Ne laser). Estimate the width of thsf56b4u+ xev se beam when it reaches the Moon.    km

  A series of polarizers are each placed at grd6r;ri).6cfs-amx cx.po ) 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 n 9q/ci 78 bshy0w/lfi$(n=1.34)$ 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 waviwx d.n yt,: n+1qzw,ues in phase with each other. They are loc yw.iq,n,t+x n:duz w1ated at 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 containing two wavelengths, 42df 66 s6,td7ovx+bilm 0 nm and 650 nm, enters a sid,dobf+6xm7 6lv t6 silicate 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 oe)cw-h( mm.va0tdlz0nu e 7t0 ne 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