Does Huygens’ principle apply to sound u8,p) ng*ndyt +2 irjzwaves? To water waves? Explain.

What is the evidence that l),bf o x-ootx.ight is energy?

Why is light sometimes described as t v8o g1m)zw:,zn)4i pm1fooa y,)qpsrays and sometimes as waves?

We can hear sounds around cornef8d.gajf ne+n +t 9d ipap6o(*rs, but we cannot see around corners; yet both sound and light are waves. Explain the differen n.d+ia gf6p(t89+f o a*pdejnce.

If Young’s double-slit experiment-dh)oc 2y ok9a+ i7daa were submerged in water, how would the fringe pattern co iady-k)d 29+7hoa abe changed?

Monochromatic red light is incident on a do00 ,q+yvbx4)(mpqs emse 9duauble slit, and the interference pattern is viewed on a screen some ,0e)y+p qbsa v49q mu0msdx(edistance 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 deix8+h/bm+ k0ygvmxtt4 *i /nustructively interfere if their path lengths difu *itxymxgm+n8+v/ /0b t4 ikhfer by how much?

Why was the observation of the double-sliyrp :0g1lw l+: :bl25rpnxv mgt interference pattern more convincing evidplgbmx0 :v g+ :r2l1w5n lrpy:ence for the wave theory of light than the observation of diffraction?

Compare a double-slit experiment for sound waves to that for lige ,fej3ggfr6aj6 3ck9emrzx1 c6 -d :fht waves. Discuss the similarities and differe9-3z jr6 g3edrj fc:cffa ekem66x,1gnces.

Why doesn’t the light from the two headlights of a distant car prozz4.m+,nbu ecch 5e(oduce an interfe, 5hm+zceb( 4c. euonzrence pattern?

Suppose white light falls on the two slits of Fig. 24–7, but one slit is cov*xr jd, 9 ;v3yxbdnc3oered by a red filter (700 nm) and the other by a blue filter (450 nm). Describe thn,xrd ; vx *ocj3bd39ye pattern on the screen.

When white light passejs7v e+fufm8 u.16z ofs through a flat piece of window glass, it is not broken down into fzfsof.vuj u8 m176e+colors as it is by a prism. Explain.

For both converging and divet8 hqack-f9h 01sk;dy+) yxdlrging lenses, discuss how the focal length for red light differs from that for vioh9h1 t ky8k c;xfdd-a0y)+slq let light.

A ray of light is refracted through three different materials (Fig. 24–5) 5 9bzb2qzk, p-xhyt;k-6tp wsiwf0 s5). Rank the materials according to their index of refraction, least to g 2twy ,x- 5hw6bsqf pi-zpbz9 0t);kksreatest.

Hold one hand close to your eye and focus on a distant light source through efxu;e-j eo2 4d* 4bmia narrow slit between two fingers. (jmed eix;*b24 fo4e-uAdjust your fingers to obtain the best pattern.) Describe the pattern that you see.

What happens to the diffraction pattern of a single slit if the l,o:mq9i(hjot g d+q9 whole apparatus is immersed in (a) water, (b) a l,9g+ tqim: djo( q9hovacuum, instead of in air.

For diffraction by a single ecj 6(z3dte-a. nj1wmslit, what is the effect of increasing (a) the slit width, awaejd6 cm 3tz(e1 .jn-nd (b) the wavelength?

What is the difference in the interference patterns formed (a) by twycw n+p)p3mtqu x*/:to 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 slitsrqv: er+ ssi77, (b) closely spaced slits+vse:rsr77q i ?

White light strikes (a) a diffraction grating, and (b) a pri8yvtc50kp3lz b. md) psm. 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 of the rainbow in each case? Explp3tlzpmb0k )dv yc58. ain.

For light consisting of wavelengths between 400 nm tbwgv51*1 dpuand 700 nm, incident normally on a1g btdu v1w*5p 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 fringess7-:l6hdiyqkvva + 9c noticeable only for a thin film like a soap bubble and not for a thick piece of glassi+hy9dasv-:q7 vckl6, say?

When a compact disk (CD) is heebx ),ya.bf:gvu ;4sg ld at an angle in white light, the reflected light is a full spectrum (Fig. 24–56). Explain. What would yoyf;b )s a:4g xg.bu,evu expect to see if monochromatic light was used?

Why are Newton’s rings (Fig. 24–31) closeraq fo;79lr2nd ;,pd w+ c,idvs together farther from the center?

Some coated lenses appear grkrjq6 im-k+x. eenish yellow when seen by reflected light. What waveleki j k+x6.rmq-ngths do you suppose the coating is designed to transmit completely?

A drop of oil on a pond/5d2 nic*v,h( e+-qnnqve tox appears bright at its edges, where its thickness is much less than the wavelengths of visible light. What can you say about the index of refractio+vqnh *-,ev xoit2nd/ cq en(5n of the oil?

What does polarization tell us about the nature of lightaj8 csdw;wx81.a kw- 8ft rw)j?

Explain the advantage of polarized sung8jiq o (a 1sp+ 81.3a8yalipgs2p wnnwlasses over normal tinted sunglasses.

How can you tell if a pair of sunglasses i(n/ +lkzpc6 gcs polarizing or not?

Two polarized sheets rotated at a,oh d:4 j cvw0:olpb6qn 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 o;3 ;yn h 0jml xfj3 cskgqc;agv7:-op7f the sky if the Earth had no atmosphere?

If the Earth’s atmosphere were 50 times denjawn( c +x6auew128wdser than it is, would sunlight still be white, or would it be some other colorw c 2nwa j(8dwexua+61?

  Monochromatic light falling on two slits 0.016 mm apart produces th1ngof:vwhmvn83l-oz bw:xxk 2+4 v4rxmm f64e fifth-order fringebv f:onz x2mol6r 18w4x gkvfn4:m vh+wmx3- 4 at an 8.8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 610 nm light is rya:oib9++lag s (l8z4tu(a dobserved 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 twotmq;) h mbn)p3 very narrow slits 0.048 mm apart. Successive fringes on a screen 5.00 m away are 6.5 cm apambqm n)p3;t)hrt near the center of the pattern. Determine the wavelength and frequency of the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of liyzk,)smm s8,0rj5* zil - s)be ezn8wdght from a He-Ne laser, with a wavelength 656 nm, falls on two very narrow slits ,swzm 5l8 bm0 8zkij)esyen*r ,d-z)s 0.060 mm apart. How far apart are the fringes in the center of the pattern on a screen 3.6 m away?    cm

  Light of wavelength 680 nm oij*ch( x, pp4falls on two slits and produces an interference pattern in which the focp* , xpjhi(4ourth-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 passesk 38zivj3ymk6 through two slits 0.58 mm apart, how far apart are the second-order fringes for these two wavelengvz3mj63ki8 yk ths on a screen 1.0 m away?    mm

  In a double-slit experiment, it is found that blue light of wavelength 460 nm gi2m) :eoooa6 kyves a second-order maximum at a certain location on the screen. :aooy)6mo 2keWhat wavelength of visible light would have a minimum at the same location?    nm

Water waves having parallel crests 2.5 cm apart pass through two openingspomv )v*qgy.j5l:*eo+gms g2 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 woujyvm*lov 5s.+ 2g)om:pqegg * ld there be little or no wave action?

Suppose a thin piece of glass is placed in frontmv0u x bhe/w 1dyop*,1 of the lower slit in Fig. 24–7 so that the two waves enter the slit/ m0 u1 e,pxhwbod*1vys 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-or5tt, +cuy un5gi qm: wb/-hk6bs5s4mkder maximum for light of wavelength 500 nm is located 12 4uysg usw,-ntqkh+/ 5ickbtmm:56b5 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 by0:6ww7kozp(q ig myar tfu/t+ -q,2f o 1.0 mm are illuminated by 544 nm light. Find the distance between adjacent bright fringes on a safttgu+( w qr70yfm i2qo,z/6-wpk:o creen 5.0 m from the slits.    mm

  Light of wavelength tso0 fk id ,rk(yc+c7)480 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 ls4ojkz m g8:*dy/ds; 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) thickness of the plastic? 8 zgs /mlo:s4dyk;j* d    nm

  By what percent, approximately, does the speed of red light (700 nm) exc(o1exf:sc1 eneed thatx1fn s :ee1(co of violet light (400 nm) in silicate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece of glass at a 60.0 6.u ua xvofh.gs2*pjf75r ns: 6fg:gm0$^{\circ}\,$ 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 ww nz83 f*nxg,mehj j(2avelengths, $\lambda_1\;=\;450\;nm$ 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 u: i7m ;8c-b cc pu63ncxs9opuc 0rko*mm wide, what is the full angular width of the central diffraction peak?co6pcrk089io;cm:s uxpu c n7b* -uc3    $^{\circ}\,$

  Monochromatic light falls on a slit thsr/poxt *p+kl gei+m9sn.-:ydznr ) *at 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 /24)0+ ki mshtoznfmtfalls on a slit that is $ 3.20\times10^{ -3}\;mm$ wide. Estimate how far the first brightish diffraction fringe is from the strong central maximum if the screen is 10.0 m away.    m

  A single slit 1.0 mm wide is illuminated by jsn+)xvv zz+2 450-nm light. What is the width of the central maximum (in cm) in the diffraction pattern on a screen 5.0 jn+ )s+x zz2vvm away?    cm

  Monochromatic light of wavelength 653 nm falls on a slit. If the angle betwg/963p8nk aai kt; slzeen the first brit3i/;a6kg sznpal 98 kght 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 av qk9j xhu- e31om*1ug screen 2.30 m behind a 0.0348-mm-wide sli m*xke3u1vu j-h9o1gq t illuminated by 589-nm light?    cm

  When blue light of wavelength 440 nmkns4 0 /e2feqg falls on a single slit, the first dark bands on either sid sn/fk0 ee24gqe 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, its+(/le xjlk13cokxc+ creates a central diffractiox joxlek1l cc(sk+/+ 3n 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 6sa3qri .4se pz-f1 ,nh50-nm light so that the diffraction maximum is 4.0 cm wide on a screen 1.50 m away, what will be the width1. -znif, 3h4prasqse of the diffraction maximum for light of wavelength 420 nm?    cm

For a given wavelengthp4( c n5t2wgnq $\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm light produce a secgv mhkm,z/e- fd.z97xond-order maximum when falling on a grm9z-/z 7.mx vkfhd,geating 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 a grating haqfn e+ qw2 :0hyveo99 ejea7op;u kset5v :z72ve if the third-order occurs at an 18.2wpq ku zh:e;s 725eej9tva e:0f+ven9q ooy70$^{\circ}\,$ 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 obserf2r7 dqtu9bnd 2 bry 5ekzo**8ved57e2 nu2dtd r8 ko b*9rbzfqy* at a 15.5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction gratinb,8 a -2)hdb prsmbqn6g 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 normallko:/ bx2d 4ehoy 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 gratingzb((udy vg6.j -4n fqx.klgs: with 6000 lines per cm is illuminated with 633-nm laser light? Assume normal incidenceuzfnly( (. v4dbsg-:k q6xg .j.   

  Two (and only two) full speczn3iy0jc,8gv e e 1bb*tral orders can be seen on either side of the central maximum when white light is sent 8 e 0gv1b,bync3j*e izthrough a diffraction grating. What is the maximum number of lines per cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containing wavelengts3l.rcfk/ b3vg (n/wahs from 410 nm to 750 nm falls on a grating with /lc k3.w/sngbr( vf 3a$8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser whiv i ,ap1 hs6-sw7-jaxgch produces monochromatic light 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 spectrum lines are measeva:t2lwc08 84iegf c. z8 kxwured 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 reflectep7iju afn44 ure8z;4zd at the centeri;np4fz 4a4 uujr ze78 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 fringes in Example 24–8 if the glass pla)v5 yuwbs)sb 1tes are each 26.5 cm longy1ub sv w)s)b5?    cm

  What is the smallest thickn:lao8m1g. 0 1 ca,dcvrker9jw rq/ld)ess of a soap film $(n\;=\;1.42)$ that would appear black if illuminated with 480-nm light? Assume there is air on both sides of the soap film. $t_min$    nm

  A lens appears greenish u1+29me5 x -eas flablaz;-vxyellow ($\lambda\;=\;570\;mm$ 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 datzen(v1 zxu:1qu ;g)mrk spot at the center) are observed when 550-nm light falls normally on a planoconvex lens resting on a flat glass surface (Fig. 24–31). How much thicker is the center than the e;me(n1 q:gu zxu)1tvzdges?    $\mu m$

  A fine metal foil separates one end of two pieces of optically flat glass, as in4xoix b;:ou*ajj m:l* Fig. 24–33. When light of wavelength 670 nm is incident normally, 28 dark lines are x* :ilxb*u;ajj4m:oo observed (with one at each end). How thick is the foil?    $\mu m$

  How thick (minimum) should the air layer be between two flat glass ) d3gv/r7b,9yb d(r(rn ua hzjsurfaces if the glass is to appear bright when 450-nm light is incid 7gvr burb)n y(,hrj(za9d 3/dent normally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, suspectednc 1crhkc,4e 5nq,eo vr7g(:r 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 alcoh-h3dy(5j+ t4ryvqzq d1a zq6fol $(n=1.36)$ 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 imw vrz /5-zmc-wy+k4 uimersed in a liquid, the diameter of the eighth dark ring decrease-4ciywmkw u5vr/zz+ -s from 2.92 cm to 2.48 cm. What is the refractive index of the liquid?   

  What is the wavelength of the light entering an interferometer i o/z-)hhp (dabf 644 bright fringes are counted when the movaazo -b d/p)hh(ble mirror moves 0.225 mm?    nm

  A micrometer is connected to the movable mirror of an interferometer. When the m. ,y;yk fwgxxzo yo/58icrometer is tightened down on a thin metal foil, the net number of bright fringes that move, compared to the ok5yyog /xwfyz8x. ; ,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 mirror *l ;o1j pcz/fhgc(td0by/o* m $M_1$ 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 srm;b+ /w; zw2lrq)dk an interferometer (Fig. 24–59) passes through a small glass container containing a cavity 1.30 cm deep. When a gas is alq)r;b+r/ zkwsw; dl 2mlowed 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 orientedadj, pd( bcs1b73na ;:nbmpfo9jr /.u,ko /cu at 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 lt).6a-e fcuz–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submerged in water if the light is hittinves kgldqvee (5nh,-j (-b4q 6g the( -ves, ebld v4qjgq5kenh6( - diamond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the light pagos g 85-;-q chvok5z ni3g8fessing through them is a maximum. At what angle should one of them be placed so that the intsei-kgn-c f3 vo8ghg 5o8 ;qz5ensity is subsequently reduced by half?    $^{\circ}\,$

  At what angle should the axes of two Po4 -g*xq 6(3 sx6enoccz+m 3bgtce rt1blaroids be placed so as to reduce the intensity of the incident unpolarrx oc+ *e66gb(-scxq4 1b3mntgce3tzized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are oriented atz,dt 3ywp0 mc xn6b7z/ 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 at 38q,.j: gxnjo *s.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 f xkb:41 +vn;kf)lllonor reflections off the surface of water for light coming from beneath the surface? Compare to the angnl +flb14k ;):v nlokxle for 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 passes thh0.qxui 7ja7ky .sc8yj,6fmy rough five successive Polaroid sheets, each of whose axis makes a . 7yjy mx.i7qk,sua6yh8 0 fjc45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength v68ljs v4t jko74 cu1v$ 5.0\times10^{7 }\;m$ passes through two parallel slits and falls on a screen 4.0 m away. Adjacent bright bands of the interference pattern are 2.0 cm apart.
(a) Find the distance between the slits.    mm
(b) The same two slits are next illuminated by light of a different wavelength, and the fifth-order minimum for this light occurs at the same point on the screen as the fourth-order minimum for the previous light. What is the wavelength of the second source of light? $\lambda_2$    $ \times10^{-7 }\;m$

  Television and radio waves reflecting from mountains or airplanes can l1t pv,vmhi0h+6ftw ;m2psod5 ,b g+minterfere with thh 2wvdt1om+v+h6 p5,,lpbsmm0; itfg e 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 diffrwfu)pz4t12 w4xpce u1action grating with 4t u)w11pxfu e zpwc24$ 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. The3c-ma: svmx+ b screen is 1.70 m away. A second source of unknown wavelength produ-bm+:vs ac3m xces its second-order fringe 1.33 mm closer to the central maximum than the 590-nm light. What is the wavelength of the unknown light? $\lambda_2$    nm

A radio station operating at 102.1 MHz broadcasts from tdsuli+z83()96dwrtn 7z b h kpwo identical antennae at the same elevation buti 968d ht up(z7+lbkrnds 3)wz 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 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 backgboin(4igy(w78jzg9 o2 a,nc from an outside doorway 0.88 m wide, and blows a whistle of frequency 750 Hz. Ignoring reflections, estiyngco9an,b8ozw4g j7 g2ii((mate 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 singlg:dd0ifvvk/ qf) ne s8h r+:c+a))nrje slit of width D at a 30$^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain bee)bok,f5d. jwi:e 2m zxn7eu8vrd3 fv2tle have a series of parallel lines across them. When normally incident 460-nm light is reflected from the wing, the wing appears bright when viewed at an anglde)kj:,nwv2m8idzfxv27 r b5 .of3eu e of 51$^{\circ}\,$. How far apart are the lines?    nm

  How many lines per centimeter must a grating h 5ewe9ui:i a5 v9+p-mtwp mhy(ave if there is to be no second-order spectrum for wa hpi5-9( wump5ti+: yme9 veany visible wavelength?   $ lines/cm$

Show that the second- and third-order spectra of white l91gv d tux(bgqd+ pz)8ight produced by a diffraction grating always overlap. What wavelengths tgux98dvq1z d(pg) b+ overlap exactly?

  When yellow sodium ln tr4 ri2 j.krm,l0e3oight, $\lambda\;=\;$ 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 with2 ++)g if +t)vrnkserd and the pattern is viewed on a screen 2.5 m from the grating. The incident light srnd+iket++ frgv) )2beam 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 150 nm thv ul rb . ixuab*;a)w:-)ukw+fickness of it, when laid on glass, is needed to reduce reflection to nearly zero when lia-wia;vkx*r )b )uwf+.u ub:lght of 600 nm is incident normally upon it? Do you have a choice for an answer?

  Monochromatic light of variab wptgk55w6 d7lle wavelength is incident normally on a thin sheet of plastic fil 5wlwdp5g7k6 tm in 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 for7gl6 wjr7ue bzb,, m/x 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 (non-zero) thickness for thckk.-njmu ldkv4wc -yyw-, lf+5kf4:06jr uoe air layer between two flat glass surfaces if the glass is to appear dark when 640-nm light is4d.-, kfj:w -k0cuklc wj4fnykrvumo6+5-yl incident normally?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the light transmitted t k.4eqc1eia (nrzkq ,)hrough a thin film layered on a flat piece of glass. Draw a diagram, similar to Fig. 24–30 or 24–3ee,cq k.4(in1 azkrq) 6, 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 horizon is the Sun when light ) +xaq*hfk/ zqreflecting off a smooth lake is polarized most strong kqxqf*)/a h+zly?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as to reduce thekb+w2.ucjuuj+b.14 l0+ c5mbbim way intensity of the incident unpolarized light by an 4bkbujci+wc . ywulajm52 m. 0 1b++ubadditional 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 wri dkm8*d9t 5*ydo ,orhose transmission axes are at right angles. A third polarizer is placed between the first two so thatt8oi5r okyd *dr9m ,*d 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 p5njs9e)oevit l-.w :s7ftc kq:1t 5mzlaced in 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 wi ) pa8 ipr(+tzdh9d(uedth 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-a(d pd )8pu(rez hit+9Ne laser). Estimate the width of the beam when it reaches the Moon.    km

  A series of polarizers are each ht-f5 ao p77 *2.rcwd9uzc flqplaced 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 iw: o/gh7fo7 z$(n=1.34)$ 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 antennasx2 0cg48so2youyw3 y i radiating 6.0-MHz radio waves in phase with each other. They are located at points3o20u4yxycw2i yso8 g $S_1$ 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, 420 nm and 650 nm, entersp ah )ypo)2ldzin,e,s/4 v7mn a silicate flint glass equilateral 27,pnhi zm ydev/),sal4onp) 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 anj67-hvrws6 gfd 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