Does Huygens’ principle apply to sound dg/ rdgr ev+* 5oug02nwaves? To water waves? Explain.

What is the evidence that ligh0f,y)pll1 yt7pw)m3v yj :jdj/n4 wz0 wscn4vt is energy?

Why is light sometimese6qm76k;mo umq6 qz1 p0z+ifi described as rays and sometimes as waves?

We can hear sounds around corners, but we cannot see a*/w atw6w50h o; doptt,p 9syiround corners; yet both sound and light are waves. wwo*0t, wd /y6;iptp5 a9o htsExplain the difference.

If Young’s double-slit experiment were submerged i(.v evvy,zwj:1i i+ zin water, how would the fringe pattern be change,:.zijv i e 1vvw+(ziyd?

Monochromatic red light is incident on a double slit, and the intera14opep t3td1ference pattern is viewed on a screen some distance away. Explain how the fringe pa3 ot 4adtp1p1ettern would change if the red light source is replaced by a blue light source.

Two rays of light from ,ruwghk xjv-xd) m 6/(the same source destructively interfere if their path lengths differ by kxm-x dwh6v,j(u)/ grhow much?

Why was the observation of the double-slit interference pattern more conving2vicbm:iy 1ika- a2 i,lf6 j5cing evidy-gi 6 2ckv5a1fj bim2 :a,iilence for the wave theory of light than the observation of diffraction?

Compare a double-slit e-y pj.b/cf g1h3zrx4l:m ryh-xperiment for sound waves to that for light waves. Discuss the simila1 jh-yr43hcxf rm zlg./:y -bprities and differences.

Why doesn’t the light from the two headligh; z2nku77s )4myrnynp ait;,9j/jgt zts of a distant car produce an interferenzn r47 nz;igy/jak)yp2 jm s,ut9;tn 7ce pattern?

Suppose white light falls on the two slits of Fig. 24–7, /q c65w adcilmk)+c, ubut one slit is covered by a red filter (700 nm) and the other by a bkicqc,d) 6cmw/ aul5 +lue filter (450 nm). Describe the pattern on the screen.

When white light passes through a flat pie16) u2ahzz wnsce of window glass, it is not broken down into colors as it z612hausw)z n is by a prism. Explain.

For both converging and diverging lenses, discuso*q4y 2 arro aqyi xm(/y0(yo4isn8 7ms how the focal length for red light differs from that for violrm 74o (x/onm(y qy0q8aoryi *y4a2siet light.

A ray of light is refracted through three different majvjt:gf0) 4qz terials (Fig. 24–55). Rank tfg 0):vjz 4qjthe materials according to their index of refraction, least to greatest.

Hold one hand close to your eye and focus on a distant light sourci /pld ,-brr2+toh1asq c,o-qe through a narrow slit between two fingers. (Adjust your fingers to obtain the best pattern.) Describ-p q 2t+1ic,qh-osdb r lar/,oe the pattern that you see.

What happens to the diffraction pattern of a single slit o pahv7mz*g f6u2 bf2+a:7hvtif the whole apparatus is immersed i2g*: 7 o+6fa b2 fh7hvvtmpzaun (a) water, (b) a vacuum, instead of in air.

For diffraction by a single slit, what ir9e wozvs/ *p*s the effect of increasing (a) the slit width, and (b) the wavelength?s/z*owv9p r* e

What is the difference in the smaj( l15r6xp 2n6zd hinterference 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 slits, (b) closelaty 2 n.**unhe/ w3ksf4jwh/fy wa.tjf3hwsun fe 42k/h**/y nspaced slits?

White light strikes (a) a diffraction grating, and (b) a prism. A rainbow appe(r6h8ln5ae7c9 qaj4 ; wai bwxars on a wall just below the direct( 48ranewiw lhj96 bqaac7x;5ion of the horizontal incident beam in each case. What is the color of the top of the rainbow in each case? Explain.

For light consisting of wavelengths between 400 nm and 700 nm, inc*ku re36vx8d d;9vt kefy+lh0ident normally on a diffraction grating, for what orders (if any) would there be overlap in the hr8 u9dxkv +ktelvy36 f;0*deobserved spectrum? Does your answer depend on the slit spacing?

Why are interference fringes noticeable only for a thin pc) ;lax-ee*z film like a soap bubble and not for azel pcx-;) *ea thick piece of glass, say?

When a compact disk (CD) is held at x:6ne 19 1+ igptav ;ka:x,inie/cdkj/ hwy6aan angle in white light, the reflected light is a ful9n+ yiw:6e knp t gvhax//k a1iex id6;:,1cajl 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 farth4geeumk14 xq:zk.en* er from the center?

Some coated lenses appear greenish yellow when seen by re6rql wn 7x7/0vs.xy ryflected light. What wavelengths do you suppose thl7/wr y7xysqnv6xr .0e coating is designed to transmit completely?

A drop of oil on a pond appears bright at its edges, where itst( rrkvi -e94s3v*wq.fn 6us c thickness is much less than the wavelengths of visible light. What can you sqi (s36tv9rfku v-r.n c*4wseay about the index of refraction of the oil?

What does polarization tell us about the natbk ln9:qxgmt d9 /kqx8,atx; -ure of light?

Explain the advantage of polarized8(r*1cgkt2 fvh3x y un sunglasses over normal tinted sunglasses.

How can you tell if a pair of sunglass ccsz*6n;w 36isrspz2es is polarizing or not?

Two polarized sheets rotated;qodq*hxizwqsq 5(l ck t0hvx x12++ 5 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 colop5- qnz n1mi6z.qj3 d) ,ayemfr of the sky if the Earth had no atmosphere?

If the Earth’s atmosphere were 50 tim2dyyf64kpm+hym bp6 2es denser than it is, would sunlight still be white, or would it be +mfyb p2 k6yyhp64d2m some other color?

  Monochromatic light falling o/07nvs;y 1bkz a cdf)fn two slits 0.016 mm apart produces the fifth-order fringe atz107d ;b avfn)/ kcfsy 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 o-- psm2j9c ;n5dc kzbdf 18$^{\circ}\,$ when the light falls on two narrow slits. How far apart are the slits?    $\mu m$

  Monochromatic light falls onpfgkl36tf 4srg( 9 ,( )jqkmcf two very narrow slits 0.048 mm apart. Successive fringes on a screen 5q6c,g flk 9(k)pg s3r(fm4 jft.00 m away are 6.5 cm apart near the center of the pattern. Determine the wavelength and frequency of the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of light from a He-Ne laser, with a w70r 1dbbio- hfavelength 656 nm, falls on two very narrow slits 0.060 mm apart. How far apart are the fringes in the center of thdb -bf0ho7ri1 e pattern on a screen 3.6 m away?    cm

  Light of wavelength 680 nm fal6 y+ ,pmvq(d /6yw(o/r(g iofkf rm;npls on two slits and produces an interference pattern in which the fourth-order fringe is 38 mm from the central fringe onyfoir r (;+nw6/ , p(6mqymp(gvodf k/ a screen 2.0 m away. What is the separation of the two slits?    mm

  If 720-nm and 660-nm light passes through 7igs4b whck38/ fcp2itwo slits 0.58 mm apart, how far apart are the second-order fringes for these two wavelengths on a screen 1.0 4pic2fcb7sh/ 8gi w3k m away?    mm

  In a double-slit experiment, it is found thfm7ilix4d1;way p 1o gi-a k,4at blue light of wavelength 460 nm gives a second-order maximum at a certain location on the screen. What wavelength of visible light would have a minimum axkdygip a4-if 14 o,17l; mawit the same location?    nm

Water waves having parallel crests 2.5 cm apart pasa/hv7mv;-r; of jx y,3 p+nhk8oapw8ss through two openings 5.0 cm apart in a board. At a point 2.0 m beyond the board, at what anglv rwojm;s8 nf-ahx,+a v8k3o h/p;py7 e 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 slit in F) z -6iua3ivylig. 24–7 so that a u63l iy)vi-zthe two waves enter the slits 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 third-order maximum for ligh v/n y5*h+dpi2pghs6( zusc,x t of wavelength 500 nm is locat,v5py/ +h(nz hsg6*spidxu c2ed 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 spot will the second-order maximum of this light be located?    mm

  Two narrow slits separated by 1.0 mm are illuminated by 544 nm light. Find the dq 66zd a/pyn4distance betwq/ 6n6dz4pa ydeen adjacent bright fringes on a screen 5.0 m from the slits.    mm

  Light of wavelength 480 nm in air falls on twh/jzu - ,g58r ht6m8kktv kzc8o 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 doubl+rn1uej u2cfq oar1mg qe/,/9e-slit apparatus illuminated by 640-nm light. The center point on the s+9j /2f/, garm ro1uecquqe1ncreen, instead of being a maximum, is dark. What is the (minimum) thickness of the plastic?    nm

  By what percent, approximately, does the speed of red light (700 nm) exceed th bz9qb v5 u)47qu.g*j e6ahxznpl8;hkat of violet light (400 nm) in vu e4bg; 5uhzk9 .8 l6zh)q7qxapbn*j silicate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece of glassq lw4+wknewo2 spf(0cty/. (j 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 c;qf56w pc5gl 1adzyd9ontaining two wavelengths, $\lambda_1\;=\;450\;nm$ and $\lambda_2\;=\;650\;nm$, enters the silicate flint glass of an equilateral prism as shown in Fig. 24–58. At what angle does each beam leave the prism (give angle with normal to the face)?
$\theta_{d1}$    $^{\circ}\,$ from the normal
$\theta_{d2}$    $^{\circ}\,$ from the normal

  If 580-nm light falls on a slit jf0bp4f5 s k r0:joyakoh,:q +0.0440 mm wide, what is the full angular width of the central diffraction peak?k 0o:p 5b,fy:hjr0 okaj4+ sfq    $^{\circ}\,$

  Monochromatic light fallhaay+c+- p0lds on 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 ohze7 vndl wsjs(8yr3z;( vd0*n 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 zjbx/g:+ ( k,axsyoz5 450-nm light. What is the width of the central maxim(kzx / b,jygz5s+oa:x um (in cm) in the diffraction pattern on a screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm fr1f* /8 lpdh fkt,qhney20ip2alls on a slit. If the angle between the first bright f h/fk8* n fpq1,te rplhy0i2d2ringes on either side of the central maximum is 32$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central diffraction peak onsqhngzd81yx *1-fkc+ 35rl a s a screen 2.30 m behind a 0.0348-mm-wi 1gx5szfdc38a l-k * rqhy+n1sde slit illuminated by 589-nm light?    cm

  When blue light of wavelength 440 nm falls on a single shlx9 1i *qvr8iqs/4kflit, the first dark bands on either side of center are separat1qri 4fl/isqk vx *89hed by 55.0$^{\circ}\,$. Determine the width of the slit.    $ \times10^{-7 }\;m$

  When violet light of wavelength 415 nm falls on qzaljb(*m.wi,it( ,zu 8o uahw ;8z4 la single slit, it creates a central diffractija,a4;wulq,z btow (( u .zli88zm*h ion peak that is 9.20 cm wide on a screen that is 2.55 m away. How wide is the slit?    mm

  If a slit diffracts 650-nm light so tha,4y:nid 3kpfvi 3 r:mmt the diffraction maximum is 4.0 cm wide on a screen 1.50 m away, what will be the width of the diffraction maximum for light ofmnpi 3mi:fr,y 3 :dv4k wavelength 420 nm?    cm

For a given wavelengo hz5uf1y om 8ovy:5nu5::vvvth $\lambda$, 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 1hq,fz-w khz ,maximum when falling on a grating whose slitsqh-fzwh, 1 ,zk 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 i w xlm6i(vuo//7oytb re+y48v8mley-f the third-order occurs at an xrbyye/v m/lm6 (i+748o 8utovw -yel18.0$^{\circ}\,$ 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 falling on a diffraction grating is observex.)x hp.iy)obd at hp.y). oxx ib)a 15.5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction grating aa3v 0ugeqp nyrf1w,z 3s04:h5u5n lr 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 p 4j. moy;dtg2on 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 spect6 p/ lqcqf+sow0*aps9 cf94saral order that can be seen if a grating with 6000 lines per cm is illuminataf* s +9 0cq6psl4pw/oas9qcf ed with 633-nm laser light? Assume normal incidence.   

  Two (and only two) full spectrahz6o m l k1og uebwby5d3(e98*l orders can be seen on either side of the central maximum when white light is sent through a diffraction grating. What is the maximum number of lines perd(b zk8 1ho59geb w3u omle*6y cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containing wavelengths from 410 nm to 750 nm fa/cgfn )9d+ek rlls on a grating withf +/n )g9drcke $8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which produces monochromatic lightq 1cd)uln1g7:. m pokt 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 spectrumx)yibpr3 xwqcm 904w:bi4+w j 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 thick, what wavelength is most stro e( xadssec;;--m3ag9uz g qx*ngly reflected at the center of the outer surface when illuminated normally by whitg(saex;s9 eda*uq;m3 g-c-z xe light? Assume that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the dark fringes in Exam yb+m9r:k- kmnple 24–8 if the glass plates are each 26.5 cm lo-m mnb kyk9:r+ng?    cm

  What is the smallest thicknesx(cmkfn rix 4w. 2l7.ls 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 green*9)x4ej (zhc pwob 1brglxdog1+p.t4ish 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 (qcfx1o2i+ pz spot at the center) are observed when 550-nm light falls normally on a planoconvex lens resting on a fla1x2o cqi(z+fp t glass surface (Fig. 24–31). How much thicker is the center than the edges?    $\mu m$

  A fine metal foil separates one end of two pieces of optically flat glaspa,z3c2 4qv hgtu6vp* s, 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 thick is tzuqp, cv36g*ta4hp v 2he foil?    $\mu m$

  How thick (minimum) should the air layer be between twwa aez:.(;dsii ,r aj3*n2ymdo flat glass surfaces if the glass is to appear bright when 450-nm n(z,y.2 :dasiw da *mi3eja;rlight is incident normally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, suspected of beuh, mfr4ey)l;sc s ,evfe )i+;ing 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 alcohss+x1xx k49id ol $(n=1.36)$ 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*fi d) 0) wnz*oea; ;1ohd1ysjr/tb9uup(rl y , the diameter of the eighth dark ring decreases from 2.92 cm to 2.48 cm. What is the refractive index of tuhp)brndo*i1d; t1y*os /l;fr z ( 09uw)eajyhe liquid?   

  What is the wavelength of the light entering an interferometer if 644 bbo 8hmwwx;lob) 03ut8right fringes o8wm8tu xb)ho w; 0bl3are counted when the movable mirror moves 0.225 mm?    nm

  A micrometer is connected to the movable mirror of an)wndmh9-a, ;c.nkp qy interferometer. When the micrometer is tightened down on a thin metal foil, the net n n9 kwnhm);d-., cpyqaumber 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 mirron9d9zzrx u6ghw,*dl +96 qtoir $M_1$ 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.ub c-eb2jr :v yp10h5i 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 fringes are counted to move past a reference line. The light used has a wavelength of 610 nm. Calculate the index of refractio- y0u h21ivj b5:pbrcen of the gas, assuming that the interferometer is in vacuum. $n_{gas}$

  

  Two polarizers are oriented b4i e ei.tq((c+gam 3sat 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 air +*z9kt8s uenw–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submerged in water if the lig4c0 p(coy5 p)cp +s 9/nf yalqk8szb+ght is hitting the ca ky+y49bp +(5lgsc)q0znc p/8ops fdiamond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the light pasq3 un )7;kjzwr 42gzajsing through them is a maximum. At what angle should one of them be placed so that the intensity is subsequently reducew 3a4;jrg7 zjzqn) k2ud by half?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as to reduce( 3rnh bxa;pfz7c l50u the intensity of the incident ua 7z(b 5c0fhlp3 x;runnpolarized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are orisu )mf8o fmlm*cvo437ented 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 a)z2v;43 rrycdtio gxbn-,k -kt 38.0$^{\circ}\,$ to one another. Light polarized at a 19.0$^{\circ}\,$ angle to each polarizer passes through both. What percent reduction in intensity takes place?    %

  What would Brewster’s angle be for reflections off the surface of.65m z ,nbxg3:jmo. l(y dkzze water for light coming from beneath the surface? Compare to the angle for totalzg,zjd m m 63yxe.l:5o.n(bzk 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-jgh8j /)pd dqli* (tv sheets, each of whose axisd jpgt* hl)8-idjvq/( makes a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength act*htp h79,h /wvzr:$ 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 fromvohqq(8 s- hn:6(m* ikrf:lh m mountains or airplanes can interfere with the direct signaohh-v(m 6lhf s* ::qmni(rq8k l 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 gr/or d7 hyg48gzating with 7gd8/ zoryh4 g$ 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. Thensv/t zh; /*db 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 light. What is the wavelength of the unknow t*nzdb;h// svn light? $\lambda_2$    nm

A radio station operating at 102.1 MHz broadcasts from two identical antennxqm 3,phm 52c5rub/ snae at the same elevation but separated by an 8.0-m horizontal distance d, Fig. 24–60. A maximum signal is found alongmrc2/q,5p 3umx nsh 5b 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, and blor:n :3mjpasx :ws a whistle of frequency 750 Hz. Ignoring reflections, estimate at what angle(s) it is not possible to hear the whistle clearly on the pla:3 rjnpaxms ::yground outside the doorway.    $^{\circ}\,$ either side of the normal.

If parallel light fab(0r*o8ypuh (ep r0vmlls on a single slit of width D at a 30$^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain beetle have a series of parallep-wskl b* - jsraa hyq+5wm(61l lines across them. When normally incident 460-nm light is reflected from the wing, the win1-ssah ( ybwajm qr+kwl-65p*g 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 a 16qgo -dl5ukop)l* fis to be no second-ord1)kulpoq5fdal-o g*6 er spectrum for any visible wavelength?   $ lines/cm$

Show that the second- and 3+y43getwh5qyi5 liguib s 56third-order spectra of white light produced by a diffraction grating always overlap. What wavelensiw+g346th5 ie b53u5yyqli g gths overlap exactly?

  When yellow sodium ligh f)h c (bm3,k(q1w y19inh 6a:r-4mvakaomcg et, $\lambda\;=\;$ 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 pattern is vz:+ w jss1;ulm/vlu0r iewed on a screen 2.5 m from the grating. wu1r0ms ;jluz+v :sl /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 r-sgg0bc ;t9n+lli7g material if a minimum of 150 nm thickness of it, when lnrl7;g i-l g+9bs ct0gaid on 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 variable wavelength is ineg 4wjal. d uw4 v036fcl/-xjocident normally on a thin sheet of plastic film in air. The reflectegd -w j0aulv/woe64x.flj43 cd 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 tu9u* xwhkct -,o.h gg4hickness 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 (nognyyker0t, 48h wcb74n-zero) thickness for the air layer between two flat glass surfaces if the glak 48n0 hyr47eg tw,ycbss 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 z)prg)/.j 0ggnut ( qu5 .mbt)a i2pwua thin film layered on a flat piece of glass. Draw a diag.n5 z(up p/mbug ar0gi)tguq))tw.2j ram, 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 hor/q3.gtwxv;h lz 4xm6xizon is the Sun when light reflecting off a smooth lake is polarized most strong/ zx x3;xw4v6qm thg.lly?    $^{\circ}\,$

  At what angle should the axes of two Polk dlsrvb2jz j0 l.*c 6smw0f06aroids be placed so as to reduce the intensity of the incident unpolarized light by an additional factor (after 6j0jflclr dmv6k . 0ss*0b 2zwthe first Polaroid cuts it in half) of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light falls on twoa:x:1 agibg) j polarizer sheets whose transmission axes are at right angles. A third polarizerag)g:i: jxa1b 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 ver*g zmvw :7ivs)tical, 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 throuhl0*h)( db gyegh a slit of width 1.0 cm and is pointed at the Moon, 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 the beam when it reac)(de y*h0hglb hes the Moon.    km

  A series of polarizers are eac tld1ywil7q- 9h 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 dm3xhn* gl t*f r6)h1y$(n=1.34)$ coats a piece of flat glass $(n=1.52)$ .How thick is the film if it reflects 643-nm red light most strongly when illuminated normally by white light?    nm

  Consider two antennas radiating 6.0-MHz radio waves in phase with each otherx)hmj ))cxxcfve6zyl149cov -r nb 58 . Thre)y9c1z fcxj5 v c84)hb 6o)x-nvmlx ey are located 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 wavelengt/ jhtat wd0/f2hs, 420 nm and 650 nm, enters a si ta2hj0f w/t/dlicate flint glass equilateral prism (Fig. 24–58).
(a) What is the angle between the two beams leaving the prism?    $^{\circ}\,$
(b) Repeat part (a) for a diffraction grating with    $^{\circ}\,$

  A Lucite planoconvex lens has one flat surface ay0aubnnqt6a(s,.2nt /nvk s1 nd 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