Does Huygens’ principle apply to sooz :t24i,x -qcldl 9uqk4p ,itund waves? To water waves? Explain.

What is the evidence that light is energy zhdbo(z7xt08 ?

Why is light sometimes described as rays and sometiuy9ea9hpb j0) -mdib/ mes as waves?

We can hear sounds around cornersp+ 7bfs8xu94h ug wfs8, but we cannot see around corners; yet both sound and light arexh wp4g9u87s 8fb+sfu waves. Explain the difference.

If Young’s double-slit experime6 5iflx(qs0l8r bd)r6t 2y 5qus2wwj ont were submerged in water, how would the fringe pattersljblt)2xd o r5sfr5uq 6(6i8w0 w2y qn be changed?

Monochromatic red light is incif vh/gph9mmn 7-l2jpci0 u /+6es(blcdent on a double slit, and the interference pattern is viewed on a screen some d-u67p 0 hcs/j9nmmllv g/pfc(i e2bh+istance 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 if their pqsd c;47s6 lq o+xssq4ath lend7 q sqs;s c4o4s+x6lqgths differ by how much?

Why was the observation of qx3q recu7d7/m88x slthe double-slit interference pattern more convincing evidence for the wave theory of light thxsl7/cq7erq 3dmu 8x8an the observation of diffraction?

Compare a double-slit experiment for sound waves torkt y +j)pc :jpry7i*6 that for light waves. Discuss the similarities an)r pi+r pjykt*yjc:67d differences.

Why doesn’t the light from the two headlip9f *n v+,vdif)g9pu;; y mxjughts of a distant car produce an interfer;d vfp* vyj g)n+x,9i; pmu9ufence pattern?

Suppose white light falls on the two slits of Fig. 24–7, but one slit issagms7+./e0 vib;n ls covered by a red filter (700 nm) and the other by a blue filter (450 nm). Descre0n/+sb. ;la i sg7mvsibe the pattern on the screen.

When white light passes through a flat piece of window glass, it is not brq+ ai0j5r 9*pi ozgw5dkl;8ldoken down into colors as it gw*o ddk5pl0iali; zj9+8 q5r is by a prism. Explain.

For both converging and diverging lenses, discusfr8sw aaw/v8ophuvbho gs/p)9)xx+n x4 ;a))s how the focal length for red light differs from that for violsogwpnp/f;v 9 )soa48x b)rau+x /vx))h8hawet light.

A ray of light is refracted through three different materiqc *5 lk(0rak (wn.kvcals (Fig. 24–55). Rank the materials according to their index of refraction, least to greate.( 5k*c c(0nkwl rqvkast.

Hold one hand close to your eye and focus on a distant light source th.4ey)c) suw+r7 3jjjbq oa3 ljrough a narrow slit between two fingers. (Adjust your fjs.cw4y r3 e)jl7bu+)jjq3 ao ingers to obtain the best pattern.) Describe the pattern that you see.

What happens to the diffraction pattern of a sinb wjd/jpyow;+( 6.xva-qp+n vgle slit if the whole apparatus is immersed in (a) water, (b) a vac jpy/pno6wq. +(d- xv+;wv bjauum, instead of in air.

For diffraction by a single slit, what is the effect of increasing (amu8z0ijdnh kc 5u)1) u) the slit width, an0uz)ih1cdnm58u j )kud (b) the wavelength?

What is the difference icqs -)u.hj3w /jz/vt in 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 advcufu.dcixd9ym5 e5sfe .(9q 0antage of (a) many slits, (b) closely spaced slfc ciydm.5q.e50uxs99d f(u eits?

White light strikes (a) a diffraction grating, and/( e yum.n/ /phoxwdb /9yo9zh (b) a prism. A rainbow appears on a wall just below the direction of the horizontal incide/.owhu/odye(znpxbhm / /99 ynt beam in each case. What is the color of the top of the rainbow in each case? Explain.

For light consisting of wavelengths betweenkqgpoy. e6p:3r- 8,mtya*l fv 400 nm and 700 nm, incident normally on a diffraction grating, for what orders (if any) would there be ove p.rv :-fapy6m glq oky3te*,8rlap in the observed spectrum? Does your answer depend on the slit spacing?

Why are interference fringes noticeable only for a thin film like vhoszw/19aw-4h w 9nu4:qoo uzcr2 0ca soap bubble and not for a thick piece of gqw:9u u 9-/hoah4nw1 o s2 wz0vcczro4lass, say?

When a compact disk (CD) is held at an angle in white light, the refl+ ny(va /n.rlih5obj6 ected light is a full spectrum (Fig. 24–56). Explain. What would you expect to see if monochromatic ly6n jl5on ar(.h+biv/ight was used?

Why are Newton’s rings ;n /u4 sv9fo,mf,omli0cj 1pd(Fig. 24–31) closer together farther from the center?

Some coated lenses appear greenish yellow when seen by reflected light. Whatt kn.9z j :g7qkg3rl-r wavelengths do you suppose the cor:j-kg9l 7. kzt3nrq gating is designed to transmit completely?

A drop of oil on a pond appears bright at its edges, where ioq9dg9 i) ucdwm2s;;m (x y/bmts thickness is much less than the wavelengths of visible light. What can you say about the index of re9d;q(;s d y9im2xc/ mu )gwobmfraction of the oil?

What does polarization tell us about the nature o:i 2ibsak+( wu jdu46tzt; +cgc2l r)yf light?

Explain the advantage of polarized sunglasses over normal tinte+cdypl kr+rkx: t,d *xhm:hq +r);oa6d sunglasses.

How can you tell if a pa .me)amy6- mioir of sunglasses is polarizing or not?

Two polarized sheets rotated at an an/sxt wsf t*,srfls/03gle 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 9itjnivpcp0 y 0)5a3lnvo:,8a .wdlb atmosphere?

If the Earth’s atmosphere were 50 times denser than i-s21/bzar bo,xtp;, 2s i5z4ug tkdrmt is, would sunlight still be white, or would it be so1gsrro4d x/zai -2mbktpz,; t 5sub,2me other color?

  Monochromatic light falling on y zg:hy 09ue/ltwo slits 0.016 mm apart produces the fifth-order fringe at an 8.8e l9uh 0y:z/yg$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 610 nm nsw d5v43(mlj light is observed at an angle of 18$^{\circ}\,$ when the light falls on two narrow slits. How far apart are the slits?    $\mu m$

  Monochromatic light falls on two very narrow slits 0.048 mm apart. b aw i;a:dpg7;Successive fri;i7g: b ;daawpnges on a screen 5.00 m away are 6.5 cm apart near the center of the pattern. Determine the wavelength and frequency of the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of light r7 o4es f0,*mh9nstcuxf zs,;):ugfnfrom a He-Ne laser, with a wavelength 656 nm, falls on two very narrow slits 0.060 mm apart. How far apart are the fringes in:z, m70n fr;g4,scoehsnu*xus t9) ff 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 interferencu, b9jh/(u;6lxe 7yhpvap xw(e pattern in which the foure(y hpx; h wlvpux7u/9j6( ,bath-order fringe is 38 mm from the central fringe on a screen 2.0 m away. What is the separation of the two slits?    mm

  If 720-nm and 660-nm light passes txd,* tg)b ;akahrough two slits 0.58 mm apart, how far apart are the second-order fringes for these two wat g;*kx ad)b,avelengths on a screen 1.0 m away?    mm

  In a double-slit experiment, it is found that blue *s-ffv,5v np2f uel-yqyf1+mgl :s .p light of wavelength 460 nm gives a second-order maximum at a certain location on the screen. What wavelength of visible 2n-+yfp u5gq-.s1s ,lmflv*pfe:fv ylight would have a minimum at the same location?    nm

Water waves having parallel crests 2.5 cm w*kqq g 826pgtapart pass through two openings 5.0 cm apart in a board. At a point 2.0 m beyond the board, at what angle relative to the “straight-through” direction would there be little op wq82qg 6gkt*r no wave action?

Suppose a thin piece of glass is placed in front of the lower slit in Fig.h85j-pfprj mff 5 cx:n+u hl0ap1l z2* 24–7 so that the two waves h18-ncfpzph2 pl5l 0m jux5:f*rfa+j 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 light of wavel ;s .0gf y0uk;qs;uzgtength 500 nm is located 12 mm from sgkuq gusyz 0.; ;t;0fthe 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 lighw2;: u0ytiq cat. Find the distance between adjacent bright fringesacqt:y2i;uw 0 on a screen 5.0 m from the slits.    mm

  Light of wavelength 480 nm in air falls on two sl fkwaqmh0 9+5a* c7lxnits $6.00 \times10^{-2 }\;mm$ 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) rm/yq):d, f yecovers one slit of a double-slit apparatus illuminated by 640-nm light. The center point on the screen, instead of being a maximum, is dark. What is the (minimum) thickne,: ydef/mqyr)ss of the plastic?    nm

  By what percent, approximag 1fgdggb5 y vh. dp8 -y9od3,rs0,xjbtely, does the speed of red light (700 nm) exceed that of violet light (400 nm) in silicate flint glass? (See Fi,bvr,ps .dx05f3odgj 1db gg-9y gh8y g. 24–14.)    %

  A light beam strikes a piece of glass at a 60.c3xs(l) 92fedw 0 ddhy00$^{\circ}\,$ 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 con t6r2qqpfkxr9c(t5;tu+ h0p l taining 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 p - z)h.l,ji khq) fs3:jzq3pi0.0440 mm wide, what is the full angular width of the cej-k zils 3,)pfh3h)q z :j.pqintral diffraction peak?    $^{\circ}\,$

  Monochromatic light falls on a slit that is jb- 4 eti slr/c-1g(2mkqyj)e$ 2.60\times10^{ -3}\;mm$ wide. If the angle between the first dark fringes on either side of the central maximum is 35.0$^{\circ}\,$ (dark fringe to dark fringe), what is the wavelength of the light used?    nm

  Light of wavelength 520 nm falls on a slit tg x+ 5/whwzw/lhat 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 ia5ubmu4+x 5 .:xadbvgq2d 6 xilluminated by 450-nm light. What is the width of the central xqv.ux bgdba2aui+654 m :xd5maximum (in cm) in the diffraction pattern on a screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm falls on a slit. Im- z xqjwy2*cq*g.i (6c /hlmff the angle between the fic*.fzm-/ 2q*wqy( jhlxcig 6mrst 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 m behind a 0.0348-mmg v67t r pu75ql8zkcocrl4e,r29(nsr -wide slit illuminated lg7qorcr ,ck2u9tr6s(lz587epn v4 rby 589-nm light?    cm

  When blue light of wavelength 440 nm falls on a single slit, the first darkd9md *c s4v0b bhlx6v5ip ,f(r bands on,d9 *bdpih bs(fl4vx0v5mr6 c either side of center are separated by 55.0$^{\circ}\,$. Determine the width of the slit.    $ \times10^{-7 }\;m$

  When violet light of wavelength 415 nm falls on a single slit, it cro6aph--s -pt zhr:t0deates a central diffraction peak that is 9.20 cm wide on a screen that is 2.55 m away. How wide is th-dtt:azp pr-06hhs- o e slit?    mm

  If a slit diffracts 650-nm light so that- io:epvr5jjkzw(tpb09-1 qg +mfw- u the diffraction maximum is 4.0 cm wide on a screen 1.50 m away, what will be the width of th9:r-jpzmp b(euw- +w5 i1-tfgkjo qv0e diffraction maximum for light of wavelength 420 nm?    cm

For a given wavelength 3f,ycr;igy/tl,ui2h $\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm lightrdjc (3huh6q- produce a second-order maximum when falling on a3chu(jq6- hrd grating whose 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(yz4w;aqh *q0 eik8k s a grating have if the third-order occurs at an 18(kk *48; qizsaqh wy0e.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 pebv)h,ijjcz/q vf2t- kv+p ;79 muh9light falling on a diffraction grating is observed at a 15.j9fvv)p/czui e-m t+h; 2v79, qhpjkb5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction grating hasa ym.t kwq t25)fmf/t7 $ 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 oktn96k g ,jb.$9700-line/cm$ 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 :mye zx(b u( 32pg*xkqspectral order that can be seen if a grating with 6000 lines per cm is illuminated with 633-nm laser light? Assume normal inciden(3qbyue*xz :2( mgpxkce.   

  Two (and only two) full spectral orders can be seen on ei;no *fynv4epxyx1 gs /,tu* m5ther side of the central maximum when white light is sent through a tyuvn14pe *gxsf5x;m /yo* n ,diffraction grating. What is the maximum number of lines per cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containing wavelengths from 410 nm to 750 nm falls on a grating witmo1o y*ot.,m ed bm6f)h tbfm6, mo).1*y odoem$8500\;lines/cm$ 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 ah)z5)k z r+gxm 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 lijtfr 1 n6ivwk*90zq ,ln(n:bines 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 strongly r;iksy8cjr7;w4ra dln-ul 7h/eflected at the cenurni ; d/a;77 4ljch8rslywk-ter of the outer surface when illuminated normally by white light? Assume that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the dark fys*o 2 i4-ly ejc4x-slringes in Example 24–8 if the glass plates are each 26sj*2 xllyys oe i4-c-4.5 cm long?    cm

  What is the smallest thickness of a n133hzw7nmtf py a4w ;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 yez5 vns )oxw4 qq*6,t-mqvvxd 9llow ($\lambda\;=\;570\;mm$ 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 countin(2 n dfnczc-8jxz2npiy/ v99f g the dark spot at the center) are observed whe982pd29-fnjcxn zyz/ n f i(vcn 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 ows)h jixdat o8*b))g d21or ,mne end of two 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 at each end). How thit)ajdrxg*s 2mb )8)ioh d1o,wck is the foil?    $\mu m$

  How thick (minimum) should the air layer be between two flat glass surfaces if ztk hb ii; vn7c;;8d7ithe glass is to appear bright when 450-nm ligz k;i87d 7;bihint;vcht is incident normally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, sx(,zu* ib,pxp, x*ecs uspected 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 alcoho90dv/k4f* ltvdu sg i3l $(n=1.36)$ 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. h0+8hfw g9yu j24–31) is immersed in a liquid, the diameter of the eighth dark ring decjg0w+98ufyh h reases from 2.92 cm to 2.48 cm. What is the refractive index of the liquid?   

  What is the wavelengthp31:m)bfhv;uv0wk h rur7 4jr of the light entering an interferometer if 644 bright fringes are counted when the movabl)r1bhu h u0;vrrwj73p:m fvk 4e mirror moves 0.225 mm?    nm

  A micrometer is connecte qr9uj o9 ioxa mmlr/3+s3u5y0d to the movable mirror of an interferometer. When the micrometer is tightened down on a thin metal foil, the net n+omxl 3r/oai09 u5u9 rj3m syqumber 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 mirro-wnr7+ :qj ijnr $M_1$ 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 (Fig3veegv,pkl(kp4vembi hq2n7 5p 44i / . 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 refraction of the gas, assuming that the interferometer is ing, m4/kpve5l2e ii7pvev nb 434 (pkhq vacuum. $n_{gas}$

  

  Two polarizers are oriented at 6uq0qf v0yan) .5$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s angle for an5 wu+ell; dze:zg2 y9z air–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diewe8c(haa :+ow b.we2 amond submerged in water if the light is hitting the dww.:w2 e e (oahea+bc8iamond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the light passing tgms3,gz6hw xno/o4 h6hrough them is a maximum. At zs/ ,o66g3mgx h4nhwowhat angle should one of them be placed so that the intensity is subsequently reduced by half?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as to reduce 6j*th5 tad f7-isafi(t0)6n l4aq6mma.i z hpthe intensity of the incident unpolarjmth6tfsi 50* n-.daqmi(6)6zalhp7fit4 a a ized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are oriented at g2f8xqhickyaf)7j tn/(y 6+f40$^{\circ}\,$ 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 atl,12 rq5qakx.nk7b cyt : pxs: 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 za y*km w+1u+jthe surface of water for light coming from beneath the surface? Compare to the angle foza+u 1+wyk mj*r total internal reflection, and to Brewster’s angle from above the surface.
If the light is coming from water to air, $\theta_{p}$    $^{\circ}\,$For the refraction at the critical angle from water to air $\theta_c$   $^{\circ}$ If the light is coming from air to water $\theta_p'$   $^{\circ}$

  Unpolarized light passevq, xd /y2a3hmumg7q5 s through five successive Polaroid sheets, each of whose axis 57d3mgva2 qu/ xqhym,makes a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength /piofv*1mv; . cha bm3$ 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 m9c; k .bpvcu9 n-jgcnht ig)-b+p :z)tountains or airplanes can interfere withb+vcup:)tt i;)gbnj9c c-z.p-h9 kn g 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 b * +wb, /scrs(*u lyii9 d+cdj54jhvathrough a diffraction grating with jsi + ascrdv d4/iy+* j5(blwc bh,9*u$ 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 ni bmhf w2 6sw+:ee85dem 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 t68b5e2 iwfe md:e+wh she central maximum than the 590-nm light. What is the wavelength of the unknown light? $\lambda_2$    nm

A radio station operatho k2zo5zw;13xd4ww4- r tu jking at 102.1 MHz broadcasts from two identical antennae at the same elevation but 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 midpoinkwo5 2jzokwz;- x4w 4r31hudtt 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 doljh)9)qn)q 74gdj q.z *dv amaorway 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 whistle clearly on dal. )hz9 )j4vqndmqag j7)q*the playground outside the doorway.    $^{\circ}\,$ either side of the normal.

If parallel light falls on a semu4lo) r h4-ade3z j 26dim.kingle 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 pfcwh *sp0d(,d arallel lines across them. When nc dhsp(0w,d* formally incident 460-nm light is reflected from the wing, the wing appears bright when viewed at an angle of 51$^{\circ}\,$. How far apart are the lines?    nm

  How many lines per cen i0 8tepwz90qgtimeter must a grating have if there is to be no second-order spectrumt0 9q wpi0ze8g for any visible wavelength?   $ lines/cm$

Show that the second- and third-order spectra of white light produced by 1ba9,6mg,bj-ui:e ,( (loydg fym x(0p ledxpa diffraction grf d d1omapu-,g bjilx0(9(xm:,g e ,y(p 6ylbeating always overlap. What wavelengths overlap exactly?

  When yellow sodium ligd f 82)x4dtjlwht, $\lambda\;=\;$ 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 vi pv,mc(au.kj 91eobm- ewed on a screen 2.5 m from the grating. The incidenucev k,.bj1a p-m9(m ot light beam consists of two wavelengths, $\lambda_1\;=\; 4.6\times10^{ -7}\;m$ and $\lambda_2\;=\; 6.5\times10^{ -7}\;m$. Calculate the linear distance between the first-order bright fringes of these two wavelengths on the screen.    m

What is the index of refraction of a clear material if a minimum of 1x. a uw,uiu.h0q rvx.150 nm thickness of it, when laid on glass, is needed to reduce reflection to nearly zero when light of 600 nm is incident normally uw ua1 xu hxurqi.v..0,pon it? Do you have a choice for an answer?

  Monochromatic light o30 g soy ysihr+b;mwc+a 2q9/zf variable wavelength is incident normally on a thin sheet of plastic film in air. The reflmyir9/;s+gba yw 20zcsqh +o 3ected 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 antvpa+q /l ycs ya3p;x5 *2zzq:ri-reflective coating $(n=1.38)$ applied to a glass lens in order to eliminate
(a) blue (450 nm),    nm
(b) red (700 nm) reflections for light at normal incidence.    nm

  What is the minimum (non-zero) thickness for the air1mc(,n z;t,p6 j0urm dnllc;:8 yaxho layer between two flat glass surfaces if tp;1x r;na0c n6m,tol8u(zdm h,:jlyche 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. si .mdio:)ln transmitted through a thin film layered on a flat piece of glass. Draw a diagram, similar to Fig. 24–30 or 24–36, and dil.s.n ) :omidescribe 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 is the Suneovu 4e yjaos2/e+2 +s when light reflecting off a smooth lake is pole oa/v2js+eu4 s o2ey+arized most strongly?    $^{\circ}\,$

  At what angle should the axes ofr/y3bjg c)so4wdl( sg4m vn)m-(* cye two Polaroids be placed so as to reduce the int4)jemlv43n ors/y gys bd*(gm (c)-cwensity of 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 eh(v+tt1 (yj:t+myh0mqma v8transmission axes are at right angles. A third polarizer is place1+m:hqj+am(mhy8( y tvtev t 0d 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 ixxiv 3uww;+t.ro8 rd1 n succession 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 of width 1.0 cm and i4rks;2cb6b x xcl5 b:f1 j lir50l:hpks 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 widtph6 s5rclcr:4f:ibx1bl5 lbk 2x;0kjh of the beam when it reaches the Moon.    km

  A series of polarizers azskq( gur)ur 8+n- 4 k0+)*8cbpl )lcxslgog dre each 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 )5oyqk ,a d l6c1g;gwj$(n=1.34)$ 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 wy ( bgb,q1;gkn+kp5o taves in phase with each other. They are locateb5k1tkp by + nqo,gg(;d 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 contai-mbvs la;aum, 6s/ )uzhehw,3ning two wavelengths, 420 nm and 650 nm, enters a silicate flint glass equilateral prism (Fig.es)-;smu/uwlaz bm,a36 ,hvh 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 surfk9, *jdbgd 2vvace 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