Does Huygens’ principle apply to sound waves? T. mpf tsi90-vqy- 8srmo water waves? Explain.

What is the evidence that l+)v-v4bt 2aga/qxmb wpci.. n6hs5oo ight is energy?

Why is light sometimes described as rays and sometimes as am3z3i ee*0, i7czglt waves?

We can hear sounds around corners, but we cannot see 5hroxi yg) yn-j h9--earound corners; yet both sound and light are waves. Explai5oy gr ---x )i9hyehjnn the difference.

If Young’s double-slit experiment were submerged in water, how would tm 50t3bicnz7 ydq+a6ahe fringe 30cmi 67a+znab q d5typattern be changed?

Monochromatic red light is 0i)f sv()*wsao4xm twincident on 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 replacewxwsa4 i 0()mso) t*fvd by a blue light source.

Two rays of light fromzboh: ah024*hry cx4g8 rtkd7 the same source destructively interfere if their path lengths differ by how mut hc2r 4rkhz g b8:ax0oh4y*d7ch?

Why was the observation ofc 8v 4xnltqi22 the double-slit interference pattern more convincing evidence for the wave ix8cn 2q4tvl 2theory of light than the observation of diffraction?

Compare a double-slit exper5t uup9q 8 o3,d48rgpnh ejkl7iment for sound waves to that for light waves. Discuss theg4htq8e lp9up u5,rnj8o7d3k similarities and differences.

Why doesn’t the light from the two headlights of a distant car produce an interag h5iz6(1 pq fe6-:dh a3pcryfer:a6r(fa6ehyg1q zphpd3 ci5- ence pattern?

Suppose white light falls on the two slits of Fig. 24–7, but one slit i61stn v2pvm.l7ndi 5wkdp5c :s covered by a red filter (700 nm) and the other by a blue filter (450 nm). Describe 2n5 ktms6iw vdcp51.7 l: npdvthe pattern on the screen.

When white light passes through a flat piece of windo xx4 nk .l5,xe//znacpw glass, it is not broken down into colorx,n/.e lc4x n/px5kazs as it is by a prism. Explain.

For both converging and db/yb.knp l4 r,iverging lenses, discuss how the focal length for red light differs from that for /pby,n.kl rb 4violet light.

A ray of light is refracted through three n;dm0.avcoi1 fs c51e different materials (Fig. 24–55). Rank the materials according to their index of refraction, least to greatest. e5c;svfo 0i1 .adnmc1

Hold one hand close to your eye and focus on a distant light source through a nktpuoi3,ff bio7r 2b7ua:20 d arrow slit betweentrf72 dp iu,akb :ub732 ofo0i two fingers. (Adjust your fingers to obtain the best pattern.) Describe the pattern that you see.

What happens to the diffraction pattern of a single slit if the4t)ur:4mo d+l3wb mqy whole apparatus is immersed in (a) water, (b) a vacuum, ins y 3bd:4m)+4owtrmu lqtead of in air.

For diffraction by a single slit, what is the efbl rgq4qv6ai wa4r:uk;5w :l*fect of increasing (a) the slit width, and (b) the wavelengt644:gurwakbq*l w5;aqvi r:l h?

What is the difference in the interference patter 3d,pl ,5bec6d1jc g )tjgy4- ctjvo-b v3j4rrns 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 ohyk deg aeuoj a 0gu(.vl)0.9-f (a) many slits, (b) closely spaced slits9g g(e)dkaho00-u lu a..vj ey?

White light strikes (a) a diffracty lk+9 v3-hgrvion grating, and (b) a prism. A rainbow appears on a wall just below the hk g+vrv93-yl direction 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 q+xh(9w(:xjj t*g7pv g epm+ nnm and 700 nm, incident normally on a diffraction grating, for what orders (if any) would there be overlap in the observed st vjnp pe* jx+ q9hggm(x7+:w(pectrum? Does your answer depend on the slit spacing?

Why are interference fringes noticeable only for a uhpt*5.e 5rbnthin film like a soap bubble and not for a thick piece opeu .5n *5rhbtf glass, say?

When a compact disk (CD) is held z5mt qxfmb mp dmy5 :+kw4k-2/at an angle in white light, the reflected light is a full spectrum (Fig. 24–56). Explain. What would you expect to see if monochromatic light was m52q m4m5dkbp:-+tyx/f m wzk used?

Why are Newton’s rings (Fnq(;slv17b:sp s:r2:yvj dw jig. 24–31) closer together farther from the center?

Some coated lenses appear greenisnhm-x0escw )4h yellow when seen by reflected light. What wavelengths do you swh -)0me4c nxsuppose the coating is designed to transmit completely?

A drop of oil on a pond appears bright at its eaa09;sh cipo+bb7z9edges, where its thickness is much less than the wavelengths of visible lighaa ;bce po9bz+i 970sht. What can you say about the index of refraction of the oil?

What does polarization tell us about the naj cl.ulf3j g9 d*y)i/sture of light?

Explain the advantage of rm+6tivaxr gy 8-xz27 polarized sunglasses over normal tinted sunglasses.

How can you tell if a pair of speub c n hio9:ixgn1: :zdc4.:unglasses is polarizing or not?

Two polarized sheets rotated at an angle7f2 e+wa dsm grts+;i6 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 i(hs+anax-bwnq3 / d 7oul93zu f the Earth had no atmosphere?

If the Earth’s atmosphdk eb5yke 4q04ere were 50 times denser than it is, would sunlight still be white, or would it be ekk b0ye54 qd4some other color?

  Monochromatic light falling on two slits 0.016 m3i/aq*r29 xi mjn lk8e4cyr -am apart produces the fifth-order fringe at q clei2xy ir*a/a-4kj rnm398 an 8.8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 610 nm light i.1 w,vmb6gt kes 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 narr ,7dg .bd)-polwmm 1nfqbv)tz80g/y fow slits 0.048 mm apart. Successive fringgom wffg.-8tb1),l 0 zdnvp7mqy/)d bes 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, wm/a8e;pw; )gge vhthx6s 7* snith a wavelength 656 nm, falls on tw eme7gpxswash 6nh;;8*vt )g /o very narrow slits 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 falls on two slits and produces an interf.f q-b8z0/mn3rsd ixu ywy(q-erence pattern in which the fourth-order fringe is 38 mm from the central fringe on a screen 2.0 m away. What is the separatuq-fy z( xybw 8isn.q0/md-3rion of the two slits?    mm

  If 720-nm and 660-nm light passes through two slij440 qvy5-eymuomqx (ts 0.58 mm apart, how far apart are the second-ox(44-q50j myo eyu mvqrder fringes for these two wavelengths on a screen 1.0 m away?    mm

  In a double-slit experimaxk18qwpcfw171 de2n ent, it is found that blue light of wavelength 460 nm gives a second-order maxf xke2dcwa711n1q w p8imum 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 2.5 cm apart pass through two openings 5.0 2x+s ;qft(ur:tlx5bl-03m l rx4myn ecm apart in a board.fyqmntlr-bx 4;+r(u:elx l02tsx m 35 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 the lower+ -*72ype/ jqhije8u9jmwdp19fdc z f slit in Fig. 24–7 so that the two waves enter the slits 182 qjpyj1fzce 9epwh j-u7dd i9/* fm8+0$^{\circ}\,$ 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 jpz6)f z -o,gyof wavelength 500 nm is located 12 mm from the central bright spot on a screen 1.6 m from the slits. Light of wavelo fp-y6g,)zz jength 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 illuminathcs 3en(q,h0 gbbnv4ct 9hi+xyl5z 5 /ed by 544 nm light. Find the distance between adjacent bright fringx5hn5 b 0cqngs +/4(y3b 9zhlitc,hv ees on a screen 5.0 m from the slits.    mm

  Light of wavelength 480 nm in air falls on two sizhpo(voysf( :g7 g0 xmx+0e6 lits $6.00 \times10^{-2 }\;mm$ 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 appatg40w2l-+ro,y ybtun59y r)ynf (n dcratus illuminated by 640-nm lf50+ dn2w9yu4- ly( n y,ctgrrbtyn)o ight. The center point on the screen, instead of being a maximum, is dark. What is the (minimum) thickness of the plastic?    nm

  By what percent, approxx pv pm q u;k,2l(a+eb2iqvu37imately, does the speed of red light (700 nm) exceed that of violet light (400 nm) in silicate flint glass? (See Fig. 24–14 2,emx(l7quiv2 vkpb q+;up3a.)    %

  A light beam strikes a ppk/a ox y/9y6bww .(txiece of 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 light connh2wb9f e3ij i dea8/3azr(i ,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 ad bp5lmd+v t(* slit 0.0440 mm wide, what is the full angular width of the ce dp(t+vdlb* m5ntral diffraction peak?    $^{\circ}\,$

  Monochromatic light falls on a slit that*i0 xt6 3nx ;+jxph6h( e8;dkwyj euba 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 520e-+urv8*aw1 x2 :wkt ktjyxb, nm falls 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 450-nm light(1z x :wt0li5doj9hbu . What is the width of the central maximum (in cm) in the diff(iw9jtulh: 0zo5xbd1 raction pattern on a screen 5.0 m away?    cm

  Monochromatic light onf y);z sk;n)pf wavelength 653 nm falls on a slit. If the angle between the first bright fringes on either side of the ce yf; zkp)nn);sntral maximum is 32$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central diffraction peak0r4qc x9*54 otdqxtsia : ;zoa on a screen 2.30 m behind a 0.0348-mm-wide slxo5:rqot;cz*t i4x40dq9sa ait illuminated by 589-nm light?    cm

  When blue light of wavelength 440 nm falls on a single slit, the firstt;c/ z n8 1e)pguysg/ var2r0nh m+3vp dark bands on either side of ccr3gzup 8 s+rhn/ at02vgmn1v)p/ye; enter are separated by 55.0$^{\circ}\,$. Determine the width of the slit.    $ \times10^{-7 }\;m$

  When violet light of wavelength 415 nm falls lkqr (:) q .uj4:cjqo;klfrf0on a single slit, it creates a central diffrac;c kf.oqqrluj rl):0:fk (jq 4tion 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 thacw3cfjyqwh ac/ ):h r;*;vs1 nt the diffraction maximum is 4.0 cm wide on a screen 1.50 m away, what will be the width of the diffraction maximc* vyn3w ;hh;s1cqacf/r:) jw um for light of wavelength 420 nm?    cm

For a given wavelengd8i0gfi cc 78hth $\lambda$, 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 2sjhw: gx6d6;trpwo4maximum when falling on a grati ghwtr js26pwxo64:;dng 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 centimeterq fy-ktvd++ h6 does a grating have if the third-order occurs at an 1 t+hd- kyq+f6v8.0$^{\circ}\,$ 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-n:5 n9ymipzjz6v 5i*nm+)zrqk sf9 2agm light falling on a diffraction grating is observe* ji5vzz sifgn+ynm z :prq5k96 9m)a2d 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 grating hasb8lbox/u7k 6p $ 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 ;vg6uw,;r ( arfjz36upqfk; q 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 orlbs brbtko/ d-6,1 )dg+xz9s xder that can be seen if a grating with 6000 lines per cm is illuminated with 633s/6 bk ),odgb -slbt19xd+zr x-nm laser light? Assume normal incidence.   

  Two (and only two) full spectral orders can be seen on either side of the cen z 90jok-8,k0deby zf(hdkm8wtral maximum when white light is sent through 9komk, hkf zdyb8d80 -z 0j(wea diffraction grating. What is the maximum number of lines per cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containing wavelengths from 41uobjhcl n bgx62 ;8 ggg9wy70:0 nm to 750 nm falls on a grating withg9ybw g8 6 jcb0:;xlhngo7ug2 $8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which produces mo3u b:ydsjm0/0yh m3xtd 1tdb6 nochromatic 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 spectr 6iqw r/+qx1zhum 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 thb1 00sf y4cakoick, what wavelength is most strongly reflected at the ceyocsf1ak 00 b4nter 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 Examplbg5m w 2tl7zw+h73,qurubb 3de 24–8 if the glass plates are each 26.5 cm 735z b3b2bw +wqt,g hl udrm7ulong?    cm

  What is the smallest thicbov:-qoqak9 ;kness 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 greenic +,i;upxtjsy 4nm)o5 sh 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 s bap-x5nf2 ux9pot 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 ce 9a -nbpxux2f5nter than the edges?    $\mu m$

  A fine metal foil separates one end of ec(ez ;mdi 4-gtwo pieces of optically flat glass, as in Fig. 24–33. When light of wavelength 670 nm is incident normally, 28 dark lines zd -e(cme4i;gare 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 surfaces xk1ja .ul7w 36ltmehr/99var if the glass is to appeavaklwu mr 3.tr7/ljh9 a1x96er bright when 450-nm light is incident normally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, suspected of bv0exp xs p6wp)gt/ :iv76 ryu)eing 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 alcohljx4-fb y wr ii(s2,-mao:2 whol $(n=1.36)$ 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(rln .o1+u i j;w7pfqd) is immersed in a liquid, the diameternlfw17 (jp q+ir;.odu of the 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 the light entering an intep9u :uy fbf5p6kmji,1rferometer if 644 bright fringes are cj59y:ukimpu1fbp ,f 6ounted when the movable mirror moves 0.225 mm?    nm

  A micrometer is connected to the movable mirror of an interferometer. When thx6r5-+qda 2 t/p faylvnsoy;4 e micrometer is tightened down on a thin metal foil, the net number of bright fringes that move, compared to the empty m2r q;x4tly/v+aap- f ody6s5nicrometer, is 272. What is the thickness of the foil? The wavelength of light used is 589 nm.    $\mu m$

  How far must the mirrk6/ *yq0aqmeh or $M_1$ 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 interferometul:4:ngf gop/ 5xjay0 :u)zirer (Fig. 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 onyjz::5 ir g/p4auxu:g )f0lgas, assuming that the interferometer is in vacuum. $n_{gas}$

  

  Two polarizers are orient/c9 ntj, xya p1hfs48led 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 -4fl8*fez73ruclr zox ld 9e- an air–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a-oo) g.xjy6l)-hmrt k diamond submerged in water if the light is hitting the ml.6y)rht- xjo gk)o- diamond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the li+h2n t*b0d+kxzt8 :r5n;dd wxi0uixh ght passing through them is a maximum. At what angle should onz02*r5t db++xuh xdni0dtw;8k hxni :e 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 the inta0x6i v9qpjevt 2jk)eighz22yw q / /2ensity of the incident unpolarizedgpjyit/ 9h6ex22v ij2)2e qvakq0 /wz light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are oriented at 40.r;; jg6qb ds 8pe7ehl$^{\circ}\,$ 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 38u; amlfm7 0 tfo*6di.y.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 ref;: .xm3dlwir blections off the surface of water for light coming from beneath the surface? Compare i: blr.xwd ;m3to the angle 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 through five successive Pa (;o*)ak3s rie(szaf olaroid sheets, each of whose axis makes a sz*o(a 3e( i rk)sfa;a45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength +l;zay yh)57ch hi7 sxyfrwe *nz9 8)c$ 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 caaqh3.kukf2fq bc0 rw l 22a6h/n interfere with theqb2f l6kh qfc.2h2 0a kwru/a3 direct signal from the station.
(a) What kind of interference will occur when 75-MHz television signals arrive at a receiver directly from a distant station, and are reflected from a nearby airplane 118 m directly above the receiver? Assume $\frac{1}{2}\;\lambda$ change in phase of the signal upon reflection.  ----待选择----constructivedestructive 
(b) What kind of interference will occur if the plane is 22 m closer to the receiver?  ----待选择----constructivedestructive 

  Red light from three separate sources passes through a diffraction grfm.0 ;v4pnp t ,ob/dp+igx: jqating with pfgn qi. x:ob v; /dp4+tp,0mj$ 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 thr*.jqs uef0m(d ough 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 0.u (s*q edmfjthe 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 two identical antennae l6-irzrjm6 7vs5 5qux 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 u r5zl76 i6 5sxjqvm-rits 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 xu5 rr8re, 3qvdc4h /pblows a whistle of frequency 750 Hz. Ignoring reflections, estimate at what angle(s) it is not possible to hear the whistle clearl3v8eurcd /rq x5ph,r 4y on the playground outside the doorway.    $^{\circ}\,$ either side of the normal.

If parallel light falls on a single sl,yl69j) old 6 5jypgevit 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 parall0n2rpa4i g7q )ualghn;)sox iz99a 2 wel lines across them. When normally incident 460-nm light is reflected from the win ip2sr2)70o ;gn9q9u )w aghi4anlz xag, the wing appears bright when viewed at an angle of 51$^{\circ}\,$. How far apart are the lines?    nm

  How many lines per centimeter must a grating have if there is to be no l:*awb7 xaxnmmq/ 9+ksecond-order spectrum for any visible wavelenamxl /9mbk+wa7x * :nqgth?   $ lines/cm$

Show that the second- and third-order spectra ou(z t2s05 rf ,tjyue5yf white light produced by a diffraction grating alwfs52( ty0u ytur 5,zejays overlap. What wavelengths overlap exactly?

  When yellow sodium light, 2pr kd 5l 2py:c)c yl o*fyb6j.wi6ji8$\lambda\;=\;$ 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)m z(;w.r)qpq x7sulf/k r: pm and the pattern is viewed on a screen 2.5 m from the grating. The incident light beam consists of twmp)q)7 qlm( r./xf:kws ru;zpo 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 materiac gc50acm em,r-yh +-kl if a minimum of 150 nm thickness of it, when laid on glass, is needed to reduce reflection to nearly zero when light of 600rm05ck-a h+g y eccm-, nm is incident normally upon it? Do you have a choice for an answer?

  Monochromatic light of variable wavelength is incident normally on a thini n2w; u;jgbv( suc-ls03tez: sheet of plastic film in air. The reflected light is a minimum only fo;(t u20c3suwn bgzv;ls i:-jer $\lambda\;=\;512nm$ 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 need5uv45 9uviqtqed 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 (non-zero) thickness for the air layer between th i8/iz.9vkcsl+ /a0hz6aato mer.8fwo flat glass surfaces if the glass is to appear dark whe+o.m 6. 8acha 9i/hr/t8ek0i vzlsafzn 640-nm light is incident normally?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the light transmitted through a t53e ne). apjtwhin film layered on a flat piece of glass. Draw a diagram, similar to Fig. 24–30 or 24–36, and describe the conditions require3 wnea5p .jte)d 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 Suwr d-bt/6b)mvvk0zw+/*gp zk:n a, i qn when light reflecting off a smooth lake is polari*w+/btz qaiz0v-/d, bk) 6wkrp:gn vmzed most strongly?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed sxh-vyc 9e+k2u o as to reduce the intensity of the incident unpolarized light by an 9hv cukxe+ -2yadditional factor (after the first Polaroid cuts it in half) of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light falls on two pbq6cpz ;3 ssxg;kj.e(.*ay riolarizer sheets whose transmission axes are at right angles. A third polarizer is placed 3b asesxi z;6rg.qcjyk.(;*pbetween 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 succes(aw)rlz4rcx )p l b,0jsion 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 is pointed at thp+7 rif qmuv2.i- 9n ad/uh+eke Moon, which is approximately 380,000 km from the Earth. Assume the laser emits waves of wavelength 630 nm (the red light7h2/idki en+- u 9+fmu.rva qp of a He-Ne laser). Estimate the width of the beam when it reaches the Moon.    km

  A series of polarizers ae vn81i1o ir3 3ivb2svre 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 *nrs5 vcit )l5$(n=1.34)$ 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 eac,6zecgg ; dizso/p8rem51x: wh other. They are located a wrezp ; xgsmo,/6:5cge8id1zt 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 containinkqwz*8d+j ;wn;yynpnd5u +x kr 4*/ c.uwya*r g two wavelengths, 420 nm and 650 nm, enters a sili d+n*zp+r5w4 rw jxaqy k; d8uny*nw;k/yc.u*cate 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 le j d;bc8fpkr4/tmx/4x upp +2edwm+1 qns has one flat surface 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