Does Huygens’ principle appl2bx bf 3i34rp/btrzb(y to sound waves? To water waves? Explain.

What is the evidence that light f- h0z19cawck 2lpk0 eis energy?

Why is light sometimes desv*;of1vqlts2*+ (7 uoilm lezcribed as rays and sometimes as waves?

We can hear sounds around corn k) vg/erc6vjjow 8(nj z02gz1ers, but we cannot see around corners; yet both sound and light are waves. Explain the di n8j wvkcgz0z(jr/1)v2og6 jefference.

If Young’s double-slit experiment were submerged in water, zb2 1h zebhj 6qicnld-p* :8(yhow would the fringe pattern be chan: qpndhh ebzjl 28b*y16 ci(z-ged?

Monochromatic red light is incident on204 ub,fsyjvu/ h- ocs a double slit, and the interference pattern is viewed on a screen some distance away. Explain how the fringe pattern would change if the red light source is replaced bysf/buv ,suc42oh -j 0y a blue light source.

Two rays of light from the same source destructivz,3 ,p1gn hv.5khhn h.p qccb2ely interfere if their path lengths differ byhb.h pz25p,nvg3kc,hh1n q c. how much?

Why was the observation of the double-slit interference pattern morgki5czu;wto 57z c3obk+ x-4de convincing evidence for the wave theory of light than the obs7giuko;35 kwb-z z5ox4d+cct ervation of diffraction?

Compare a double-slit experiment for7rrvntjf hrqm b. q(7(1icw6 vj,ve .) sound waves to that for light waves. Discuss the sib(r7f(wjehcj.,1 rq)i .v7r6nvm qv tmilarities and differences.

Why doesn’t the light from the two headl u0 k;jaee(4 goj/*wsjights of a distant car produce an interference pattern?0*w(g4ju eso aj;je/ k

Suppose white light faly. /exph-aq;elnub .dp+2 tq+ ls on the two slits of Fig. 24–7, but one slit is covered by a red filter (700 nm) and the other by a blue filter (450ux2 p ++q.;ypeqnlha/e. t-bd nm). Describe the pattern on the screen.

When white light passes through a flat r9 cemst j2+65i)z,b(2qu0ya hi rhtt 3og2mbpiece of window glass, it is not broken down into colors as it is by a9u26b mgtrh omh2rytjsb,3 0 5 (act2ieqz+)i prism. Explain.

For both converging and diverging lt*0 eq v4a(jhgb1k2cpenses, discuss how the focal length for red lighgk *pjc (va 21tbe40hqt differs from that for violet light.

A ray of light is refracted through three different materials (Fig. 24–55). R1x j t;6m3iaiqank the materials according to their index of refraction, li m1;tqx3 6ijaeast to greatest.

Hold one hand close to your eye and foj dn4 meq1i 2yv8:wmt2g7 qof+cus on a distant light source through a narrow slit beif nwqvm2:+j1 7yqg demo4t28 tween two fingers. (Adjust your fingers to obtain the best pattern.) Describe the pattern that you see.

What happens to the dir8ii-:vh,ptlxv*ww3a iq4 .tu*, dw affraction pattern of a single slit if the whole apparatus is immersed in (a) water, (b) a vacuum, instead of in a ,ia*qir 8 xt l,thv4widwa*u3w: .pv-ir.

For diffraction by a single slit, what is the eff- 3v, hf(skhluect of increasing (a) the slit wius(hf kh-,3lv dth, and (b) the wavelength?

What is the difference in the interference patterns formed (a) by two slits6 ta/fre*ms8cgp7uk 2o, 9jbo $^{-4}\;cm^2$ apart, (b) by a diffraction grating containing $10^4lines/cm$?

For a diffraction grating, what is touc8 bo +7fbr/,- wtbghe advantage of (a) many slits, (b) closely spaced sg/ 8cf b7ur+,t-wboo blits?

White light strikes (a) a diffraction grating, and (b) /wmwl .c7wno 4a prism. A rainbow appears on a wall just below the direction of the horizontal incident beam in each case. What is the color of the top/w47nw. c owml of the rainbow in each case? Explain.

For light consisting of wavelengths between 400 nm and 700 nm, incident normally/ yy+7co)bpv e b+o yeyc/vp 7)on a diffraction grating, for what orders (if any) would there be overlap in the observed spectrum? Does your answer depend on the slit spacing?

Why are interference fringes noticeable only for a thin fil hnb-zl:2-hfy/cl0 y egk/c 6f(r; kuhm like a soap bubble and nkkh(n h/0 yr:fe hb/;6flu-gcc2lzy -ot for a thick piece of glass, say?

When a compact disk (CD) is held at an anr/ pcej svtwu) jwa695vbrfp9* xx: /7gle in white light, the reflected light ie) px7*f: t rc9j wvj/9x/sa6vbpu5rws a full 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 from the *2 cvh3:d vy msk);risdk (9jd-5iap lcenter?

Some coated lenses appear greenish yellow when seen by reflected light. What w+8rqbg844gnb b lju2hrr)z+ f avelengths do you suppose thz + 4u rb8frr8bglj n2gq4)+bhe coating is designed to transmit completely?

A drop of oil on a pond appears bright a+p+skg )e9el: )erufht its edges, where its thickness is much less than the wavelengths of visible light. What can you say about ug h)rf klpee+ 9es)+:the index of refraction of the oil?

What does polarization tell us about the nature of li qy-50z beuk5/yyvfk7ght?

Explain the advantage of polarized sunglab x6 eaj0r1/0sv cpwe+sses over normal tinted sunglasses.

How can you tell if a pair of sunglasses i tjhf:*ul7pn :rii w1+s polarizing or not?

Two polarized sheets rotated at an angle of 90tysk;a900vhht g xcn:djrje:s u1 my /j)05p7$^{\circ}\,$ 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 Ea o.1zk lb*4brbetm90 hrth had no atmosphere?

If the Earth’s atmosphere were 50 times denser th9/4np uvat7sm0q ym -of7ho-l d 0svo:an it is, would sunlight still bef ssmn p7yvodh40v0-:o/o a l9tumq7- white, or would it be some other color?

  Monochromatic light falling on two slits 0.016 mm apart produces tx j ajw;7sz9u*he fifth-order fringe at an 9as;u j*zwx7 j8.8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 610 nm light is obsebf s4ks),q.44tg u5zwv(yf cwrved 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 narx+*n dp )xi c4sqy tv9qqfj5(yjb8-+ )opoed -row slits 0.048 mm apart. Successive frinn8td- )4jx-d 5)q 9c*ieyypb(pj +xf+q qvoosges 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 from a He-Ne laser, with a (sp,*ygrqhpi-f de9 v7c v:0kwavelength 656 nm, falls on two very narrow slits 0.060 mm apart. How far apart are the fringes in the center of the pattevi 09 fqp-v cs*(,kr7dehgyp:rn on a screen 3.6 m away?    cm

  Light of wavelength 680 nm falls on two slits and produces an interfes6nci.d; ozd)rence pattern in which the fourth-order fringe is 38 mm fr) zocdn6s; d.iom 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 through two slits +;1ai aq dpf/dm- iz m/ y7pmn*9cyxk:0.58 mm apart, how far apart are the second-order fringes for these two wavelengths on a scryc/dnz97y ixk 1mmamq:fa /di *p+p ;-een 1.0 m away?    mm

  In a double-slit experiment, it is found that blue light of wa57l,pa 2s0dh(prhs+pm ds i s.velength 460 nm giv(hsmppa.h05+ssdd ril, 7 ps2es a second-order maximum at a certain location on the screen. What wavelength of visible light would have a minimum at the same location?    nm

Water waves having parallel crests 2 v k*w8a.3t9so3x eghf.5 cm apart pass through two openings 5.0 cm apart in a boatx afes .8 v3w*ko3hg9rd. At a point 2.0 m beyond 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 is placed in front of thf.6aa d9wb5vest9j - re lower slit in Fig. 24–7 so that the two wave -r9e6dswfa jvb59.t as 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 li4qix 4ntb 5d;k- ml:ydght 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 spot will the second-order maximum of this light be 5ydq xib t:klm;n-d 44located?    mm

  Two narrow slits separated by 1.0 mm are illuminated by 544 nm ligl3hy 4oeq:gp;hhq c gp;u03*bht. Find the distance between adjacent bright fringes on a screen 5.0 m frope* 0gq l;hq3g:h;ubo43y chpm the slits.    mm

  Light of wavelength 48r,3u sc370wo,do0/l jdyoa v l0 nm in air falls on two slits $6.00 \times10^{-2 }\;mm$ apart. The slits are immersed in water, as is a viewing screen 40.0 cm away. How far apart are the fringes on the screen?    mm

  A very thin sheet of plastic (n=1.60) covers one slit of a double-slit apparatv,:n2f w2g8jl(yv 7tz d9 ypvkus illuminated by 640-nm light. The center point on the screen, instead of bei y8twvlgvy: ,2n zp7fkvd 92j(ng a maximum, is dark. What is the (minimum) thickness of the plastic?    nm

  By what percent, apprsz81 pc7 pk4e*oaz ix a)-bu6zoximately, does the speed of red light (700 nm) exceed that of violet light (400 nm) in sisazxip uzp7 4) ab*1eozc8 6-klicate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece of svc. qo)-zj f- 69bie8atp ko,glass at a 60.00$^{\circ}\,$ incident angle. The beam contains two wavelengths, 450.0 nm and 700.0 nm, for which the index of refraction of the glass is 1.4820 and 1.4742, respectively. What is the angle between the two refracted beams?    $^{\circ}\,$

  A parallel beam of lighxcwrp dc2zg-2q2 w+o5t containing 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 0.0440 mm wide, wha(ly cjgv d))k8py0-kct is the full angular width of the cen8)cjk(lkv p 0d)yyc-gtral diffraction peak?    $^{\circ}\,$

  Monochromatic light falls on a slit t2 t-9kqsm5 7znmtpd p*hat 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 a st:yb6-b 7bcy flit that is $ 3.20\times10^{ -3}\;mm$ wide. Estimate how far the first brightish diffraction fringe is from the strong central maximum if the screen is 10.0 m away.    m

  A single slit 1.0 mm wide is illuminated by 450-nm light9h buqd 7smkl cs57g.wu0aopl, 1;ht-. What is the width of the central maximum (in cm) in the diffraction pattern on a screen 5.0 kdu-q7g 5.cmh w 7b,os ult1haps 09;lm away?    cm

  Monochromatic light of wavelength 653f2siyw3(ne65;vi7)h-ar hwm0z hj ut nm falls on a slit. If the angle between the first bright fringes on either side of the central mawz3ysu 6 2nrhhefih 05v-wta ; 7(ijm)ximum 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-mm ivwt;km y4k5p(s8hg l6ww30j -wide slit illuminated by 589-nm liy5kl; (iw064svw8gwpmjhk3 tght?    cm

  When blue light of wavelength 440 nm falls on a single slit, the first dark*:os1-ie /wk d+gt bjq bands on eithej:qi+ / ewg*ts1od-k br 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 sing3alk7c5ye o2q3b-f jn le slit, it creates a central diffraction peak that is 9.20 cm wco7qk yb53e 3 2jnf-laide on a screen that is 2.55 m away. How wide is the slit?    mm

  If a slit diffracts 650-nm lighxa97 tjv4g6:6fisapkv ; + dplt so that the diffraction maximum is 4.0 cm wide on a screen 1.50 m away, what will b9p g6fp:a+xtd 7 4vkvsija6 ;le the width of the diffraction maximum for light of wavelength 420 nm?    cm

For a given wavelengt1v:qqgrtl3: lo0v5 6ar pg d;uh $\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm 6cw dwf+2f3dmzi lth:ynh, )s i r 08:z)z;hrxlight produce a second-order maximum when falling on a grating whose slits are0+h2fwzi 8rz6w mhn;x): 3hf dzc)tr:,syld i $1.45 \times10^{-3 }\;cm$ 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 occurs at nhs hyg-ewt*1qqzz(9 j ;r+)m an9erwth)+z1n- *(; yqgmqshzj 18.0$^{\circ}\,$ 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 fall f*xw44nv ays;ing on a diffraction grating is observed a*;vx4y f4n swat 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 hy.e2,x. m;z7 k xfm9d+g yn,etmrd u:yas $ 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 normal tnu,,kgmli2m /njk4,ly 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 spectral order that can be seen if a gray ;0p o3ezcah/ting with 6000 lines per cm is ill;a pcy3/o0hezuminated with 633-nm laser light? Assume normal incidence.   

  Two (and only two) full spectral orders can cpof0)+fo4.se5nr ff 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 per cm for the gratinfco)s rf0p4o fn +e.5fg?    $ \times10^{ 3}\;lines/cm$

  White light containing wavelengths from 410 nm rq; th ftsj/-4rcb 5l1+h/xno to 750 nm falls on a grating with n-+s o qb ;5/h/xl4jhtc1rr tf$8500\;lines/cm$ 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 a kn 5ivkos2tt /e1d+f8bi own wavelength $\lambda\;=\;6.328\times10^{-7 }\;m$ is used to calibrate a reflection grating in a spectroscope. The first-order diffraction line is found at an angle of 21.5$^{\circ}\,$ to the incident beam. How many lines per meter are there on the grating?    $ \times10^{ 5}\;lines/m$

  Two first-order spectrum lines 90fxox 6lqdkcf -9cd/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 gf/5n ma+ 1nz7x i)m nc1nrv1xm,c/x0vh 1nxg120 nm thick, what wavelength is most strongly reflected at the center ovg)x,7r nxn/ /1ci cx m 1mnnz50 vhxn+1m1gaff 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 fringfie:bi3h p7 gtnf 53z2l;8p jaes in Example 24–8 if the glass plates are each 26pplz 8f:t n3a2;ii 7e bg3h5jf.5 cm long?    cm

  What is the smallest thickness ou0** qqgat6e ,0seyzhf 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 yellowxlk:(g w:21-co gvydg ($\lambda\;=\;570\;mm$ 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 (hl4z / d ;kvil hskjzeqxo74:d2ii.8hu-, )b gnot counting 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 t-2;udvil 4jbi7h.ix kh:hzqo 8d),/s gk z l4ehicker is the center than the edges?    $\mu m$

  A fine metal foil separatesex,y m/nk8/sw one end of two pieces of optically flat glass, as in Figm/8esn w/ yxk,. 24–33. When light of wavelength 670 nm is incident normally, 28 dark lines are observed (with one at each end). How thick is the foil?    $\mu m$

  How thick (minimum) should the air layer be between two fu,cwx9c7hku*(f2 6x j v- 0 uf.ineszqlat glass surfaces if the glass is*hnucq,s fzewc6x-f uv i jk97.2x0( u 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 being a stf)c6nd7 8glw jolen 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 alcoholyihvvcv*k;. 8 $(n=1.36)$ 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 approz3 6 bf*o8;ug ffkli4j1ez2aratus (Fig. 24–31) is immersed in a liquid, the diameter of th8 2u1 g;j63fzloork fzbfi4e*e eighth dark ring decreases from 2.92 cm to 2.48 cm. What is the refractive index of the liquid?   

  What is the wavelength of 7hr6c olp2m a9z7s53zz9dmq u the light entering an interferometer if 644 bright frilr9c u5 o7mszah3 72p z9d6mzqnges are counted when the movable mirror moves 0.225 mm?    nm

  A micrometer is connected to the movable mirror of an interferometer. When 8b-aa6)7i.8kjjy tg fjha rf 3the micrometer is tightened down on a thig68)ja y87t- ijjfkh 3aba.rf n 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 mirrol nd:+v ugsymd6y,j bf89)jl4r $M_1$ 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) passes throug d,*dedyi9yk14 voiw/* dzc n+h 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 refractv /z,*cw9ieydko+4ddn i 1d*yion of the gas, assuming that the interferometer is in vacuum. $n_{gas}$

  

  Two polarizers are origrszu 09+rn g/ dd)b)7xahb5f ented at 65$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s angloh wh .aq(js1u56a(ofe for an air–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle fp vf :hik5;((3lzoqhnor a diamond submerged in water if the light is hitting the diamp5:(q;hlhfz3n oi(v kond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the light passing through them is a maximum.(-ybr60 fk s9;iu,u e7u wlluy At what angle shouu (skl uu,el b 7;0-yfu9iw6yrld 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 shy 1qbj,oo-h41f;q u fo as to reduce the intensitbhqf fo1,-;hu y1ojq 4y of the incident unpolarized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are oriented at 4n0 d1ik3zf)r c5+yr gx0$^{\circ}\,$ 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 or bgh2j uf9yq5/o 87zrpiented 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 su+ zd6xe b2l6mjrface of water for light coming from beneath the surface? Compare to the angle for total internal reflection, and to Brewster’s angle frombxle2j +6d z6m 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 successi+3xel 8 2ihohh9yr oz:-fgwv /lx, zh(ve Polaroid sheets, each of whose axis make/+(zhh x wfo:8v2xehohgz 3, iy-l9 lrs a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength )r:a2cnb h 2*znguj+k*gvg7 m$ 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 wav q7sm*t oljvl9p+20 dwes reflecting from mountains or airplanes can interfere with the direct jqpdto0*w2 9sm+7l vl 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 thrcsq ys7r7l;bssya -ws+ + k5ihgl) y35ough a diffraction grating with sai k -rhs7yc wll;5y+y+)g 7bsss5 q3$ 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. Thecrqt9q )f st/7 screen is 1.70 m away. A second source of unknown wavelength produs)qc9/7tr f qtces 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 atnws 2gc:a+5 ml 102.1 MHz broadcasts from two identical antennae at the same elevation but sepan5w a2mcs:g+lrated by an 8.0-m horizontal distance d, Fig. 24–60. A maximum signal is found along the midline, perpendicular to d at its midpoint and extending horizontally in both directions. If the midline is taken as 0$^{\circ}\,$, at what other angle(s) $\theta$ is a maximum signal detected? A minimum signal? Assume all measurements are made much farther than 8.0 m from the antenna towers.

  A teacher stands well back from an outside doorway 0.88 m widbsjtwyj- ,iz;fz:h .4 e, and blows a whistle of frequency 750 Hz. Ignoring reflectiotwz -ifj,sj4 .y; :hzbns, 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 slit xdzv) k(h77+.nz toxaof 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 linecvr ik0gp:8 k )dznyid5p;,i. s across them. When normally incident 460-nm light is reflected from the wing, the wing appears br8id znp:k;di5,grypv0i c .k) ight 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 sec2*pccn5gtyt 3 ond-order spectrum for any visible wavelengy53gnt t*pc2cth?   $ lines/cm$

Show that the second- and third-order spectra of white light producp tscu8+5n az8ed by a diffracti+cu8nzt8ps 5aon grating always overlap. What wavelengths overlap exactly?

  When yellow sodium light,8ay8j j.ye) /yx awikye;5yr* $\lambda\;=\;$ 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 viewedzk 3 *oshmax8k95 9uvl on a screen 2.5 m from the grating. The incident light beam consi8k 95umolzkxsh * v3a9sts 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 mmvrpy60t9dczd c/ 4k,inimum of 150 nm thickness of it, when laid on glass, is needed to reduce yv6dmpr/t4c, z9k0 cd 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 wavelen//igu 8uphr x6gth is incident normally on a thin sheet of plastic film in air. The reflected light 6pgru 8hx//iuis 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-reflec-dj*2l9fi hfutive 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 air layer between two fla3t9 h6 cl 9 rahpd/l4ir2*yfyit glass surfaces if t 9r4ty9p*lyi 2hh3dcfalri6 /he 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 transmitte6fwvgb0:l+gto;iw+ *b dtqs3 6 hik)ad through a thin film layered on a flat piece of glass. Draw a diagram, similar to Fig. 24–30 or 24–36, and describe the cond6t ot; bisgl3wk 6q+vf)ab+dwg: 0* ihitions 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 Sun whzx7d+2 o rdc z4on,3bsen light reflecting off a smooth lake is polarized most strongly?x o7 2,+r3zddcsbn4oz    $^{\circ}\,$

  At what angle should the axes of two Pohv.0mvj-wjy+ *g t ,iolaroids be placed so as to reduce the intensity of the incident unpolarized light by an additional factor (aft i +h0jt*.,mv wov-gyjer the first Polaroid cuts it in half) of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light falls on two polarizer sheets /;,oo j*/jzrxb6p.e(rj3soc5pvmyg whose transmission axes are at right angles. A third polarize oo grj(/j.mp3rsoxbvj z/6 ,5p *y;cer 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 ,n.yah6dz*rl 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 te hr s rx*v)4k/n.zk1mhrough 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 wavelengtzek/rxrs )h.n4mv *1kh 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 pn kmeg k5w1*n4laced 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 2t/grjtf; ,mz $(n=1.34)$ 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 65a pt04kzuow5dl j bk;0w 4+e):ni dze.0-MHz radio waves in phase with each other. They are a;z )4okujnwtwz4 p:5dei0kebl+0d5 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 wavelengths,k dzdklgh 0g4p+9k 57v 420 nm and 650 nm, enters a silicate flizgd5l+k79gvp h 4dkk0nt 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 vwnpz+s;*.7mx:gjas 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