Does Huygens’ principle apply to souk;ac1z9o1t)i5/ wekt51 qt qv u-srcu nd waves? To water waves? Explain.

What is the evidence that lightfj y 5si6:1eb ur5 1eshzvc/t) is energy?

Why is light sometimes described as rays and sometimdxj -eopy* :f2mr7-gz es as waves?

We can hear sounds around cornersxsn4,g 1ds+v p xwq2;x, but we cannot see around corners; yet both sound and light are4pdv,xwg ;1qsns 2xx + waves. Explain the difference.

If Young’s double-slit experiment x+yex y i:,u,;,uwmcswere submerged in water, how would the fringe pattern be chan ixm+y:;ewuu,,s,x c yged?

Monochromatic red light is incident mq z-wg/ny;w4on a double slit, and the interference pattern wmq z/ ;gwn-4yis viewed on a screen some distance away. 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 iitxpsj5wa4 dw q* l*mlz7e,67f their path lengths differ wwl*e*7sm5 6 4ztxpd lij7a,qby how much?

Why was the observation of the double-slit interference pattern more convincib 9jz7776 bvjg fwb46sxwkl n)ng evidence for the wave theory of lb7s4w)7f 76kv jx bg 9jlb6zwnight than the observation of diffraction?

Compare a double-slit experimentr,kjq )fbd ,eq.+;mnvg b2g j4 for sound waves to that for light waves. Discuss tbke jq;.gn4 2,v)m fjgb +,rqdhe similarities and differences.

Why doesn’t the light from the two headlights of a distant car produce ahe-m l0 hwg0b6rz1/bn n interference pa0 zbehwblh-1 0ngrm6/ ttern?

Suppose white light falln 1yz) +zx;m9zi.dwv fcr3.qis on the two slits of Fig. 24–7, but one slit is covered by a rzmy nz.w+cid)39 vqfx;.z 1ried filter (700 nm) and the other by a blue filter (450 nm). Describe the pattern on the screen.

When white light passes through a flat qk 1lemh8 wlw gkcj4hp ei70v6v0.)5bpiece of window glass, it is not broken down i0wk0) q 47lemlj18pc h5he kg6iv.bvwnto colors as it is by a prism. Explain.

For both converging and diverging lenses, discuss hhmf.. m5 bs q;8ghzhr3ow the focal length for red light differs from that for viols5rh3mb qzghfh .8.;met light.

A ray of light is refracted throughjs5cob3 )z mg9 three different materials (Fig. 24–55). Rank the materials according to their inc9b3smojz 5g) dex of refraction, least to greatest.

Hold one hand close to your eye and focus on a distant light sou.ccvw3 0:+jx2ca- * o-oe (gvmxts tntrce through a narrow slit between two fingx2s eg otwo+t0( xtc-jm3:v-.* can vcers. (Adjust your fingers to obtain the best pattern.) Describe the pattern that you see.

What happens to the diffractiugf( +;e pizg3on pattern of a single slit if the whole apparatus is immersed in (a) water, (b) a vacuum, instead of in aigg3p euz+; f(ir.

For diffraction by a single slit, what is the effect zeb3,3/m md x (cfz(5skeyvp*of increasing (a) the slit width, and (b) the wavemf*p5ybze, dx 3 kevz 3/c(ms(length?

What is the difference in the interference patterns formed (a) bydzwr *xbv0kd66iu+o 5+j a,aa two slits $^{-4}\;cm^2$ apart, (b) by a diffraction grating containing $10^4lines/cm$?

For a diffraction grating, what is the advantagecp4 cn ;0g8qsi of (a) many slits, (b) closely spacedc iqp80n;s4 gc slits?

White light strikes (a) a diffyqeq3: kpsl1xm513piraction grating, and (b) a prism. A rainbow appears on a wall just below the direction of the horizontal incident beam in each case. 31e1x5y 3 qsipmqlp:kWhat is the color of the top of the rainbow in each case? Explain.

For light consisting of wavelengths between 400 nm and 700 nm, inciy+khx.0nps) lj tj/i7dent normally on a diffraction grating, for what orders (if any) wo0hnj.s pl7)j+tx/ i kyuld there be overlap in the observed spectrum? Does your answer depend on the slit spacing?

Why are interference fringes noticeable okir ib0* -elants0k45iuw4 *only for a thin film like a soap bubble and not for a thick piec ns iu-00w5o*atik4ki4l*ebre of glass, say?

When a compact disk (CD) is held at an angle in white light, dgb(cje x 3l; uq0n-e.the reflected light is a fule0 (cgebxu qd3l ;.j-nl 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 together farther fro.a3r gh;fn:dd m the center?

Some coated lenses apqqmnn )1sm)u 4 m2prd,pear greenish yellow when seen by reflected light. What wavelengths do you suppose the coating is designed to transmitn,)rd 4m) pmn2u1sqmq completely?

A drop of oil on a pond appears bright at its edg7/f,xlqau r)idly-5vfk+ a 1 res, where its thickness is much less than the wavelengths of visible light. What can yo/vdfrr f+k yxl-ql)ia7 ua,15u say about the index of refraction of the oil?

What does polarization tell us about the nature sz(7( aqf)na9v9nf ksv59jvby+4 out of light?

Explain the advantage of polarized sunglasses over normal tinted jk+s 6u856;gagl cxuesunglasses.

How can you tell if a pair of sunglasrhgm96 :eh u-/j/l 7a+bxbwlpses is polarizing or not?

Two polarized sheets rotatewg54v5d4c ; s;ebavaqf- zf j / r:dqd-j.;uqed at an angle of 90$^{\circ}\,$ with respect to each other will not let any light through. Three polarized sheets, each rotated at an angle of 45$^{\circ}\,$ with respect to each other, will let some light through. What will happen to unpolarized light if you align four polarized sheets, each rotated at an angle of 30$^{\circ}\,$ with respect to the one in front of it?

What would be the color of the sky if the Earth hpy*z9i9 asze8ad no atmosphere?

If the Earth’s atmosphere were.u+aobu3hxf 5 50 times denser than it is, would sunlight still be white, or would it be some otu+. ax5b3oufhher color?

  Monochromatic light falling on two slits 0.016 mm apart prf( j7ym o z(v7s4hw+zsoduces the fifth-order fringe at 7h4w zs(+zfv( oysmj7 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 kh-m0o1 r it:ban 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 ver*fno:al1dq zm* c+2 5wpkem2p y 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. Determine the wavelength ak po aeq* 2* 1+wpc5:2mzdmlfnnd frequency of the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of light from a He-Ne laser, with a wavelength 65 3qkp fm0dxozp /x;k)26 nm, falls on two very narrow slits 0.060 mm apart. Howdfx 3 ;2pxkoz/)0pq mk 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 slitsm n4yl)2 eygwuiada )2::peo ; and produces an interference pattern in which the fourth-order fringe is 38 mm from the central fringe on a screen 2.oe:): gwp24 il muda2y e);nay0 m away. What is the separation of the two slits?    mm

  If 720-nm and 660-nm light passes throug4upz t(j 3.wt:3qtk fuh two slits 0.58 mm apart, how far apart are the second-order fringes for these two wavelep(:ftj t34. zwqu 3kutngths on a screen 1.0 m away?    mm

  In a double-slit experiment, it is found that blue light of wavelen mmi8,5s0bcts2 t )zdggth 460 nm gives a second-order maximum at a certain location on the screen. What wavelength o cd t0,2)tsgmiszm5b 8f visible light would have a minimum at the same location?    nm

Water waves having parallel crests 2.5 cm apart pass through two opening s g4(x; s9rq6h1wkhqws 5.0 cm apart in a board. At a point 2.0 m beyond the board, at what angle relatiq (1q whrs6;94gkxshw ve 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 slit in Fig. 2g dxy+4+ *gypd4–7 so that the two waves enter the slitsg*dxp4y+gy+d 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 experimec27q q ffle,d(jc97y lnt, the third-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 wavelengfjd7l,ye f q7( q2c9lcth 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 .qsg hg12k:nt5 f;gpo by 1.0 mm are illuminated by 544 nm light. Find the distance between adjacent bright fringes on a screen 5.0 m from the sli;fk.gg 5n:hp s12 goqtts.    mm

  Light of wavelength 480 nm in air falls on twomgzd.;k2yj 5ec5c hwxffyu/ ep +52)s 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 of a double-slit 5 q/ *inb4 8yq0ckw+ti couo,yapparatus illuminated by 640-nm light. The center point on the screen, instead of being a maximum, i8co qkn4 w/obt+y0qui5 *cy,is dark. What is the (minimum) thickness of the plastic?    nm

  By what percent, approximately, does the speed of red light (700 nm) exceb*h;t ijcemnow *t,/ .ed that of violet light (400 nm) in silicc *j*.to ie,m;tbnh/w ate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece of glas,liql 2+h *onfe72ndx + )dtzas 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 wavelengthsw:+-.ilz ztwo:vj vpx4u4ne*, $\lambda_1\;=\;450\;nm$ 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 ytf0-n wd tqy,1 3 5cy4uznl2bslit 0.0440 mm wide, what is the full angular width of twnd ny 1,qy2c-lb0 ztu tfy543he central diffraction peak?    $^{\circ}\,$

  Monochromatic light falls q 1n*nfr *dg sjbu*d*( 7;mr6iggbj.yon a slit that is $ 2.60\times10^{ -3}\;mm$ wide. If the angle between the first dark fringes on either side of the central maximum is 35.0$^{\circ}\,$ (dark fringe to dark fringe), what is the wavelength of the light used?    nm

  Light of wavelength 520 nm falls on 3w:(l,a ea ,dm2w jwjna 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 45vewy5:z e5spebq6t+5+ xzi w +0-nm light. What is the width of the central maximum (in cm) in the diffraction pattern on a scree:sipzexz5weybe6vt q+ 5+5w +n 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm falls5a)igo6+y7 baed+gp xa ( tv)o on a slit. If the angle between the first bright frinpoxv)aa+gibta 6+go ( 5yd7 e)ges 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 m behind a 0.034 ku;5mvil 2k6h8-mm-wide slit illuminated by 589-nm l5ui k2v k;mh6light?    cm

  When blue light of wavelength 440 nm falls on a singy)/ ,0k vm uqgcj2nh1+4aqfjy. w4q-vcy 1sytle slit, the first dark bands on either sidcuf atjvq+4y 0.4-qk1g y syh,q 1v2)n wymj/ce 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, ir (qu4wky0e)b0uo nc5 oz4xe 1t creates a central diffraction peak that is 9.20 cm wide on a scre5k zcw41 r0oobye4qxn)0u e( uen that is 2.55 m away. How wide is the slit?    mm

  If a slit diffracts 650-nm light so tha 9 cp1yj5b6pdat the diffraction maximum is 4.0 cm wide on a scre p19a6b 5cpydjen 1.50 m away, what will be the width of the diffraction maximum for light of wavelength 420 nm?    cm

For a given waveleng)6is8io+1 2c agj kndith $\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm light produce a s1li*jeq7p .h3rr9q4 v pzdb/s econd-order maximum when falling on a grating wdq7 pvi*./q9hzb3rr4e 1 psjlhose 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-order occuut/g 8n1 hvx9q5/g demrs at an 185u9/x v8gtq/eh1n dgm .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 rmadox bx0*:wxkt /qamc -6.+falling on a diffraction grating is observed at a tkcq amx+w-m0/ 6.oxba:*rdx15.5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction grating h-d5wv(e ae k4 5r:vwmn)t ta6jas $ 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 7yzvhn ,,obqrb*m 0c+ $9700-line/cm$ 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 b/l .2frswly9/ pdi43tyk jc0ce seen if a grating with 6000 lines per cm is illuminated with 633-nm laser light? Assume normal.2c9 3j 0y ps/kw/cyifldtr l4 incidence.   

  Two (and only two) full 3r-nax5 5.jeyz olq,uxy(a(gi)ou* n spectral orders can be seen on either side of the central maximum when wh)nauox (*5j5-zei3qrny lx o .ga,y(uite 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 wavelengt -,ys.4s khckbhs from 410 nm to 750 nm falls on a grating with ,s -kb4y.kchs$8500\;lines/cm$ 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 3tplg5r2hh- +gs bc+s 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 spectralbmts,z(1e nb- s14eum lines 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 t:w dqag-o i4uzv4dm,;hick, what wavelength is most strongly reflected at the center of the outer surface when illuminated normally by white ligh-uia4:dd mvz o;g4 wq,t? Assume that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the dark fringes in 7y)vkumb hq2c*y8t 0a Example 24–8 if the glass plates are each 26.5 cm l*km)72ubyacvq0 ty h8ong?    cm

  What is the smallest thickness of a s )wx isiz w431j,v:p,kph d4whoap 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 green*d8ipkxpn,0lr x-zd /bxww/c: 0vi 50f;bvzcish yellow ($\lambda\;=\;570\;mm$ 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 ;v8eos6+sdb4 q d;(vpgo6hs gspot at the cen+s6bs8ge 4vdp6(ogv;dsh q o;ter) 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 piece8:qea.i jnf 9ss 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 at each end). How ten f9j 8i:qs.ahick is the foil?    $\mu m$

  How thick (minimum) should the air layer be between two flat glass surfaces i psgvk,4 zjpts; 9w+8mf the glass is to appear brigh4vm9+wj ;8psg kz spt,t when 450-nm light is incident normally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, suspected of being a sto1zo 9v*9 fdgdzdp5z q81e75 z i0gwjl+4veqqwlen 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 alcoholbcb ml,cdkhe9q-8o56 $(n=1.36)$ 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 dianxe)x dh74lzp5, oec (tnv.h* meter of the eighth dark ring decreases from 2.92 cm to 2.48 cm. What is the refractive index of the lih vd),7(nzpt xl*hc 4oene5x. quid?   

  What is the wavelength of the light entering x5ag +sbt fx,e5i24ac an interferometer if 644 bright fringes are counted when the movable mirror moves 0.225xx,a54 t+gace 52ifs b mm?    nm

  A micrometer is connecte,w-1h s m;zm 2qyziyg)be9( xcd to the movable mirror of an interferometer. When the micrometer 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?w xbm)- s yyz1hezm;,(c29gi q The wavelength of light used is 589 nm.    $\mu m$

  How far must the mirrorv h, e8+/eljad $M_1$ 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) j3k s7escrt4bx v..n+svf(. 2xyhtcx9 s7r:cpasses through a small glass container containing a cavity 1.30 cm deep. When a gas is allo hr7y3b s xe2txs 4v(cfv cnx9sck.t..j:s+7r wed 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. Calculate the index of refraction of the gas, assuming that the interferometer is in vacuum. $n_{gas}$

  

  Two polarizers are oriented at z vqx5-y* o58c)u rmdyg8sn-q65$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s angle for an air–guk6bu pyd48hhh )d 3,ilass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle *u crdpud(rbn3l. /5 zfor a diamond submerged in water if the light is hitting the dia5*u cd lrr /pu3(b.dnzmond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned r(1s5gofoq pg, ,2li7 2jinc8gjq-sd so that the light passing through them is a maximum. At what angle should one of them be placed so that the intensity 1n jqpr7ssd5 ,c o 228oqfgglj,-(i igis subsequently reduced by half?    $^{\circ}\,$

  At what angle should5 vbk;xe-ve(u m a,5dp4j+ naw the axes of two Polaroids be placed so as to reduce the intensity of the incident unpolarized 5jv( e a;mv-udebkaw n4x+p,5light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are orientedc vw.nge g6c45 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 o3gbxf p vty5p)*i(sr ,riented 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 j 0rk2r;qh k/u3t0 jeisurface of water for light coming from beneath the surface? Compare to the angle for total internal reflection, and to Brewster’s angle from 0tihj0/uk r jr; ke23qabove 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 th *oid 1y*o:tku 6mmn6mrough five successive Polaroid sheets, each of whose axm*u*16myn d:tok6 io mis makes a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength lvk p8p0f8sl5(q his 2$ 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 waves9i+y nyn3o ohhd*y..h reflecting from mountains or airplanes can interfere withy.9oon 3d y.+iy nhh*h the direct signal from the station.
(a) What kind of interference will occur when 75-MHz television signals arrive at a receiver directly from a distant station, and are reflected from a nearby airplane 118 m directly above the receiver? Assume $\frac{1}{2}\;\lambda$ change in phase of the signal upon reflection.  ----待选择----constructivedestructive 
(b) What kind of interference will occur if the plane is 22 m closer to the receiver?  ----待选择----constructivedestructive 

  Red light from three separate sources passes through a diffraction gratiqnax*z: z)1qk uh8 l0dng with zq:8au xlqnhd0 *zk1)$ 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 59043j(8pnw3h2en ovga rnan 0/c nm passes through two narrow slits 0.60 mm apart. The screen 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 lighvo0(ejnan2hpnnr c 83/3gw 4at. What is the wavelength of the unknown light? $\lambda_2$    nm

A radio station operating at 102.1 MHz broadcasts p qjba3t)l(y, xdat; 5from two identical antennae at the same elevation but separated by an 8.0-m horizontal distance d, Figxab5d3t; tpqy()l , aj. 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, andz(tbu w hj-s,8 blows a whistle of frequency 750 Hz. Ignoring reflections, estimate at what angle(s) it is not po t h8w(jbsz-,ussible to hear the whistle clearly on the playground outside the doorway.    $^{\circ}\,$ either side of the normal.

If parallel light falls on a+7kr ; y t+.bkac9 jt06ywusnb single slit 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 lines across them.7/ -4rx sm *jcd mdw0*rg)qulv When normally incident 460-nm light is reflected f0/)ujqr*r gc7s4mx*vd lw dm-rom the wing, the wing appears bright when viewed at an angle of 51$^{\circ}\,$. How far apart are the lines?    nm

  How many lines per centimeter must a grating have if there is to be no seconn3vlxph *3ccdxi1p0t+z,sg(d-ordercpd(+*xcsg,iv phl1 30txn z3 spectrum for any visible wavelength?   $ lines/cm$

Show that the second- and third-order u jdt q*;eckw(ct6:o:spectra of white light produced by a diffra:cw;6(kt d:o *ecujqtction grating always overlap. What wavelengths overlap exactly?

  When yellow sodium ligi-j m1pnqgw qkzp6y0 ,z,h3a6 ht, $\lambda\;=\;$ 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 aaxi s4omdt k.2t4un ))nd the pattern is viewed on a screen 2.5 m from the grating. The incident light beam consists of two wavel.xti))kmusanot d 4 24engths, $\lambda_1\;=\; 4.6\times10^{ -7}\;m$ 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(a p1uw*w /lf4tao 7.p dadak/ clear material if a minimum of 150 nm thickness of it, when laid on glass, is needed to reduce reflection to nearly zero u*a(fd71awatp op da .kw/4l/when light of 600 nm is incident normally upon it? Do you have a choice for an answer?

  Monochromatic light of variable wavt0(oh+ q/0brwj9 +pw e tcvq9kelength is incident normally on a thin sheet of plastic film inbjvwq9 0 r tpec 0woq+h9k+/t( air. The 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-reflective coy eb 0 ktrv061q:txi01xz(kxxating $(n=1.38)$ 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 flat glaih2m5 )pm r+sywg3uw9ss s+)py 25swuim 3w9hmgrurfaces 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 thro hga*nrd- *y8zugh 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 for maxima and minima. Consider all possible values of index of refraction. *8yharzd -*ngDiscuss 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 refle8nz 5:7mfh- gpthx+ h9mlu g8wcting off a smooth lake is polarized mosgl htgf:8n5 hm-9w m7+ zxp8hut strongly?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as to reduce b z0:dny++p aofv(y-jt*z ei.af4fa *the intensity of the incident unpolarized light by an additional factor (after t0+ *t*v+f :fz.- anypf4ibaeoy dja(z he first Polaroid cuts it in half) of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light falls on two polarizer sheets whosa6 +og,uze .ojp8xkj.e transmission axes are at right angles. A third pola8+z j oxk6jg, euo..parizer 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,/o f)hcq u4dp 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 m)loueyeu y d22m0 b,9of width 1.0 cm and is pointed at the Moon, which is approximately 380,000 km fromye2lo bu92my,e0m du) 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 pl1c.2nxr/,qeascr (0vwplni 0 aced 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 -j+ un-)lzzkxd3b 2 ej$(n=1.34)$ 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 w; f*n y4w +l-0wxwunomith each other. They are located at pointx +;-wnf4wow u0 nm*yls $S_1$ 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 ligh e.b2c5ofv h*rb/hfq7t containing two wavelengths, 420 nm and 650 nm, enters a silicate flint glass equilateral prism (Fig. 24–58bfe7f o q.bvc*52hhr/).
(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 szyvu-he)oa5w52ll c8 ksm- q4urface 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