Does Huygens’ principle apply to sound waves? To water waves? Expl:;vh3wkg ro33i(cmc *uhpyg r2b*0oaain.

What is the evidence that lightum3kqg-w3l k)x t/ g0o is energy?

Why is light sometimes described as rays and somet82ukra iw53.mx vf2u ilk 5y-uimes as waves?

We can hear sounds around corners, but we cannot see ar2/7ggle fji+ pa xh50sound corners; yet both sound and light are waves. Explain th+e7ash 20 f/ glgjpi5xe difference.

If Young’s double-slit expe 6vibaba)w tr+f3es9r+ )rjoj+8 r7vdriment were submerged in water, how would the fringe pattern be cha7 i rajr83ae++t)6v+dvj)b osf9rrb wnged?

Monochromatic red light is incident on a double slit, /q3eafwdrb29dw1ck*.m k9 maand the interference pattern is viewed on a screen some distance away..q9k91acd e2fw kw/m3 mdrba* 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 theiha.+t zxt( )plr path lengths differ by t.p(xh )t+zl ahow much?

Why was the observation of the double-slitx* h8sjyrl ttb/s6a4l(f v( *j interference pattern more convincing evidence for trtsl8 sb6(ljj*(* /h f ayvx4the wave theory of light than the observation of diffraction?

Compare a double-slit experiment for sound waves to that for light;kd/dx )kit,ipu-,pmd 1/ gbc waves. Discusx/ ,p)/tddcdi mu, ibk p;kg-1s the similarities and differences.

Why doesn’t the light from the two headlights of a d u4o) rib)x(skj(m1u9z,.noo fh1 gstistant car produce an interference patturs(s1.ot mkxi4j)g (foohu),9 1 zbnern?

Suppose white light falls on the two slirhvd 7 tn8v0y-*+a2z b6 ofymbts of Fig. 24–7, but one slit is covered by a h r va6*yfm27ty d+ob0-8vzbnred filter (700 nm) and the other by a blue filter (450 nm). Describe the pattern on the screen.

When white light passes through as;cmoe4rq 1d hp2aie ar r25n *ir,s*. flat piece of window glass, it is not broken down into colors as it is by a pr.rhpi2 nq54c rm,1 res oes*da; ar2i*ism. Explain.

For both converging and diverging lenses, d spgcv9m 9a*k3iscuss how the focal length for red light differs from that for vim39cv pas* g9kolet light.

A ray of light is refracted through three different materials (Fvz;w sl mukfz ps;(fix x;,a13*+u- ixujo/d+ ig. 24–55). Rank the matersiuua ;* 1u+s;v;z- + wzpxmjo,lx3f( d kif/xials according to their index of refraction, least to greatest.

Hold one hand close to your eye and focus on a distant lightye4r(x:+g ygs source through a narro (:gsyrgx+4yew slit between 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 sd+v1v.peg4 xir9- xozt k n3a9lit if the whole apparatus is immersed inr9tkvad z-43o. p eix19+gvxn (a) water, (b) a vacuum, instead of in air.

For diffraction by a singla9ulk6 9zsd76qz hlx.o,:s ile slit, what is the effect of increasing (a) the slit width, and (b) the waqi 9z:s.,9shz6k6l l 7oxa lduvelength?

What is the difference in)+ dvnf b4:nln 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 advantage of (a) many slits, (b) closelhg7uynd0g g13 r :hp*o:)udlzy spaced s7g*:dnh pouhz)31 lug yg0dr: lits?

White light strikes (a) a diff; 1ydfaj ow/dtv; h0:z: +pessraction grating, and (b) a prism. A rainbow appears on a wall ju:tj;ae:; +0 z fs /dhvpsowd1yst below the 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 4003ek2 q--yyk bqlfq:j9l0p 2hx nm and 700 nm, incident normally on a diffraction grating, for what orders (if any) would there be overlap in the observed spectrum? Does your answer depend on thq0qlb ef3yj qp92 ly-kxk-:2 he slit spacing?

Why are interference fringes noticeable onpnijzk76mp; 8 3s(esv ly for a thin film like a soap bubble and not for a thick piece of glasss7;38pe6kspmvi j z(n , say?

When a compact disk (CD) is held at an angle in white g w.lnxx;q-s; light, the reflected light is a full spectrum (Fig. 24–56). Explain. What would you expect to see if mox;-q xl;w.gs nnochromatic light was used?

Why are Newton’s rings (Fig. 24–31) closer togetbi)h:7wwn n k 4qbek30her farther from the center?

Some coated lenses appear g0+lqlbk (-b lxp6or s+reenish yellow when seen by reflected light. What wavelengths do you suppose the coating is desigk0x-(bblq 6r+ olls p+ned to transmit completely?

A drop of oil on a pond appears bright at its edges, where its i: deyp(0qv*kmb;dx1ybqj:;x dm/m7thickness is much less than the wavelengths of visible light. What can you say about the index ox 70qmy b/;m(b*qjd:;mpkdiey: dxv1 f refraction of the oil?

What does polarization tell us kvv+mcy70d3 h about the nature of light?

Explain the advantage of polarized sutwy qy *i) srd*uq1l,/nglasses over normal tinted sunglasses.

How can you tell if a pair of s7w)wegh7f v3sdg6(dvefn 9)lunglasses is polarizing or not?

Two polarized sheets rotated at an ::dzvjdll8 +k 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 of the sky if the Earth had no atmospherj9a/ l3hoiun 6 4yu1hye?

If the Earth’s atmosphere were 50 times denser than it is, rt u m8kb nkv b/)xz7d,ev6-0iwould sunlight still be white, or would it be some other colore/xbi0-db nk)trvv8 u 6mz,k7?

  Monochromatic light falling on two slits 0.016 mm apart produces the fifthbc u7sv)pq,vj5(/bqd -order fringe at an 8q bqdcp/( u,vs)7j5vb.8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 610 nmm+g r;thzqm3exa 9:7, iwwfm. 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 vpsw*;llg+g o*15 et usery narrow slits 0.048 mm apart. Successive fringes on a screen 5.00 m away are 6.5 cm apart near the center of the pattern. Determine the wav5l 1l+pggou et*s *;wselength and frequency of the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of l3 5xo eh:ebc2be z1t-nsar2 ) vi(fi:pight from 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 the center of the pattern on a screen 3. :fz cop2xbn2arei :(ish1 )5 bvete-36 m away?    cm

  Light of wavelength 680 nm falls on two slits a(o;hmp9s dps* 9,i dwcnd produces an interference pattern in which the fourth-order fringe is 38 mm from the central fringe on a screen 2.0 m away. What is the separation of the two s(,p9cmiwspo ; dhds 9*lits?    mm

  If 720-nm and 660-nm light passes through two slits 0.58 mm eizr +/zrd-z8apart, how far apart are the second-order fringes for these two wavelengths on a screen 1.0 m away? 8-zrzdz/ rie+    mm

  In a double-slit experiment, it is found that blue light of wavelen 81u21 7vyztm6wilmzl,mr/ ungth 460 nm gives a second-order maximum at a certain location on the screen. What wavelunt 8y6l1 7izl/, mm rvz2muw1ength of visible light would have a minimum at the same location?    nm

Water waves having parallel crests 2.5 cm apart pass throuo gruk-4lo )6uvb,) kryma c*02kc/wsgh 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 or no wave aows,g amukl/c)4 2u)o6c vrky0kr -b*ction?

Suppose a thin piece of glass slel ( kvst/f/y(4 b(m.+s-l nrkd8zgis placed in front of the lower slit in Fig. 24–7 s 8(zs+kl m e .bflv4/-y(kldstrg(sn/o that the two waves enter the slits 180$^{\circ}\,$ out of phase (Fig. 24–57). Describe in detail the interference pattern on the screen.
24-7
24-57

  In a double-slit experiment, the third-order maxi lqs,):ex46-t(j,hyxofv w qimum for light of wavelength 500 nm is located 12 mm from the ceny(w-x oh 6sl,)4e: q ,fvtqjxitral 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 54/,(p5u nf.yqwqozs+s4 nm light. Find the distance between adjacent bright fringes on a screen 5uz/,f+n wps(5. qqsy o.0 m from the slits.    mm

  Light of wavelength 480 nm in air falls on g4 dc9llq rr48r jb,4*jsd(ob 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 plasr:(x*w2srg0k05g (uamzd 7 sy l(qfd xtic (n=1.60) covers one slit of a double-slit apparatus u5rm7g (d f (qxg x:0z w*(skrsy0l2adilluminated 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?    nm

  By what percent, approximately, i2s+*x*4nhon j)h:i xkgtw.d does the speed of red light (700 nm) exceed that of violet light (400 nm) in o* )hgdxwjhnskxi:4n+*2 t.isilicate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece ofux,u9w1 s9/zwd cd.q 5ik8xzv 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 containing h :y 7p;lizre(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, what is the fu k;abuefnyc pfhxd.+ 8 ts;z9ii2x:5 :ll angular width of the central diffraction peyfes9bia n2hc5ip.u x;txz kd ::8; f+ak?    $^{\circ}\,$

  Monochromatic light falls on a sly8h9 emrblr0p(8 ssv8it that is $ 2.60\times10^{ -3}\;mm$ wide. If the angle between the first dark fringes on either side of the central maximum is 35.0$^{\circ}\,$ (dark fringe to dark fringe), what is the wavelength of the light used?    nm

  Light of wavelength 520 nm falls on a slit th:gezv vxi;8t(zstcg 93u - o,yat 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. What is the widthk .cobel9px5 * of the central maximum (in cmeo59x.*kp lc b) in the diffraction pattern on a screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm falls oru 8o8cnc-ps79 u rq8fn a slit. If the angle between the first bright frru rcufc q8p89o- 8sn7inges 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-mtva6u7 ms*8bub4 tt-fg.ff3 t m-wide slit i4a6 tfuft8 tb gsmt3 bu-7.*vflluminated by 589-nm light?    cm

  When blue light of wavelength 440 nm falls on a single slit, the first dark baq8.:j:a sr,jgidsa: f3rar8 woe4uo9nds on either side of .a8rojgq o8uj: eiras4s d:w93rf ,:acenter 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 sl)3sz4n0jz g(5kir uz 2elz/jiit, it creates a central diffraction peak that is 9.20 cmzi) z(/k5ej03rjgn4 izu 2 lsz wide on a screen that is 2.55 m away. How wide is the slit?    mm

  If a slit diffracts 650-nm light so that the diffrap48cen 3t;rt qction maximum is 4.0 cm wide on a screen 1.50 m away, what will be the width of the diffraction maximum for light of wavelen pt;8ct3re 4qngth 420 nm?    cm

For a given wavelength )e c8hf x,cdmggb03j2$\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm light 5ypk0ksawz7t l*kyf q mz)94mki 8pb ,2j se:,produce a second-order maximum when falling on a grating whose slits k4jp wfszt,,)l2 i05e m :kzy a8b*qkk9myps7are $1.45 \times10^{-3 }\;cm$ 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 tauvg77fi 8(tc -rrji. hird-order occurs at an 18au 7( r8v-gt7.cfiirj.0$^{\circ}\,$ angle for 630-nm light?    $ \times10^{3 }\,lines/cm$

  A grating has $8300\;lines/cm$. How many complete spectral orders can be seen (400 nm to 700 nm) when it is illuminated by white light?   

  The first-order line of 589-nm light falling on a 7rwcf e91z; tbdiffraction grating is observed a1bte;wrf 79czt a 15.5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction gratinnfm -vmmb r0jvxkj :)oe47y ;1g has $ 6.0\times10^{ 5}\;lines/m$. Find the angular spread in the second-order spectrum between red light of wavelength $ 7.0\times10^{-7 }\;m$ and blue light of wavelength $ 4.5\times10^{-7 }\;m$.    $^{\circ}\,$

  Light falling normally on d,kfqr9aonk :z9 7vla44q) x*5 fgxfb 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 gratier6orzh4lk1l p65 j+rchd(8i ng with 6000 lines per cm is illuminated with 633-nm laser light? Assume normal inchi+rpc8 61 zho e45rl6(rjkld idence.   

  Two (and only two) full spectral orders0s+- qw agjhr-j tf5(m can be seen on either side of the central maximum when white light is sent through a diffraction grating. What is the maximum number of lines per cm for t-j-ahfm0+ tgj5 rsqw( he grating?    $ \times10^{ 3}\;lines/cm$

  White light containing wavelengths from 410 nm to 750 nm fal ;uj z2c(h:c6m:sk evbrhd60p )xb)jqls on a grating with uxech bsjbr;)6pd) c6kq (:hz:v0j2m $8500\;lines/cm$ 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/ex hy nr8 2zcm- trb0w++rhz5own 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 a 4 8/nwug(cjelines 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, whatfg 99c26rwh+oowk:zp wavelength is most strongly reflected at the center of the outer surface when illuminated normally by white light? Assume p okrwh9 z+fog w69c2:that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the dark fringes in Exam8h pepwi)abdj2a bw;9k3a1z 6ple 24–8 if the glass plates are each 129jka bbpwai)de6wp;3 haz826.5 cm long?    cm

  What is the smallest thickness of a soap fi6 f f/kjpgtvdx74nd9c ncf uqe9 .)5-wlm $(n\;=\;1.42)$ 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 as wvp;c.w*e;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 Newtg zo ss0:o+ej3on’s rings (not 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 thicker is the cenez os0s3:o gj+ter than the edges?    $\mu m$

  A fine metal foil separates one en:ax*hmtqvlooquh 2;3m1z, k9d of two pieces of optically flat glass, as in Fig. 24–33. When light of wavelength 670 nm*hmq x 2tz,: ;ovqao3kumh1 9l is incident normally, 28 dark lines are observed (with one at each end). How thick is the foil?    $\mu m$

  How thick (minimum) should thexe9v(,h gg0jf69 xz ns air layer be between two flat glass surfaces if the glass se6,g 0zg(n9f9x jxvhis 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 sd9gwh/kfbtr.u rcs2f0 8a6(q tolen 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 x:p 8czp4ld. qemb/f1sa:u eu+):qhfol $(n=1.36)$ 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) tyj1)g ;3is )5tld6snjhr; sp is immersed in a liquid, the diameter of the eighth dark ring decreases from 2.92 cm to 2.48 cm. What st;)s6rjt 3h)ly1;jngp5 sidis the refractive index of the liquid?   

  What is the wavelength of the light entering an interferometer if 644 brightn5/5qm 3+l ravcj: hiqff6 3(fw s(8tbc4zzwr fringes are counted when the movable mirror moves 0.225 m4/z 8:ilwbr f q+nqfjvm53wzr3cc((s6f 5ahtm?    nm

  A micrometer is connected to the movable mirro jp q.xhrf/j)*r of an interferometer. When the micrometer is tightened down on a thin 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 wavelenp/qfh* j.) jrxgth of light used is 589 nm.    $\mu m$

  How far must the mirro6kcdp(/gb p9b r $M_1$ 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 anep;yj t;9 ok1gln( iw: interferometer (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 wavel l:kwp;9( njti1e;oygength of 610 nm. Calculate the index of refraction of the gas, assuming that the interferometer is in vacuum. $n_{gas}$

  

  Two polarizers are ori fq:kv 2ya53ts;yz ta ;v f ho66*y1y,mzya6ciented at 65$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s ang8e/i3fkd,moyyp3i/ r pnc (h 5le for an air–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submerged in watesut o+fvy50b fz;y*u r2pv.9e r if the light is hitting the diat o 95b;*p+uvry.u2fz0sve fy mond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the light passing through themocgr6( t8u . oymrp::v is a maximum. At what angle sht8.om:vrou y: gr6 c(pould 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 the intnvu/ a3ad92ydw.6 q .kz;dpe sensity of the incident a2k3z.qd.n a6;u9ewdy p svd/ unpolarized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are oriented at hj.h:dk.2m9 hh9.t pe - nmilp40$^{\circ}\,$ 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 38a r- 9jcb fz (ymxpa-y6(2b p0w4mx1mn.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)can s z7*cr t59yvnz4 angle be for reflections off the surface of water for light coming from beneath the surface? Compare to the angle for total internal reflection, and to Brewster’s angle from above the surface. )a z*7 4crsn zcntyv95
If the light is coming from water to air, $\theta_{p}$    $^{\circ}\,$For the refraction at the critical angle from water to air $\theta_c$   $^{\circ}$ If the light is coming from air to water $\theta_p'$   $^{\circ}$

  Unpolarized light passes through five successive Polaroid sheets, each of w;: dh6cwr/3nyp5t slwhose ax:pyd nr;5thc/wwl36 sis makes a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength iw;*o )g g,8 hlv2ow8nymlp-p$ 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 q1a0wpo x:.z e6i( 6uydrep;bcan interfere wi 6op6b;xuqae0ie(r:wdyp.1 z th 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 separateeg)du;h ) svopyna* hv )x70q* sources passes through a diffraction grating with uvdqo))y)7sx;h 0a *e*phnv g$ 3.00\times10^{5 }\;lines/m.$ The wavelengths of the three lines are $ 6.56\times10^{-7 }\;m$ (hydrogen), $ 6.50\times10^{ -7}\;m$ (neon), and $6.97 \times10^{ -7}\;m$ (argon). Calculate the angles for the first-order diffraction lines of each of these sources. $\theta_{h}$    $^{\circ}\,$ $\theta_{n}$    $^{\circ}\,$ $\theta_{a}$    $^{\circ}\,$

  Light of wavelength 590 nm passe r,px)yoe5mz. tk9 - 8pimj.tfs 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 the central maximum than the 590-nm lightz yi-,.x8ptmf5o)pj k .mret9 . What is the wavelength of the unknown light? $\lambda_2$    nm

A radio station operatine0hwk)buuo /+g 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 o)0bu+w/k euh. 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 yuojb r1 ;)3nc0.88 m wide, and blows a whistle of frequency 750 Hz. Ignoring reflecu)y3c;obn rj 1tions, 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 7ec*i )dys)dv r75 jzhslit 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 parallel lines *g a7b-ibq)3j6 n wloxkd8tn*across them. When normally incident 460-nm light i dgwbqa3 7kotnj8b6xn* )i*- ls 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 centimeter must a grating have if there is to be no second-oomhnh:z q8 xa5+4rg0d +j o0uzrder spectrum for any visible wavelengtoha8+:jz u 4gx 0mdo0nz5qh+r h?   $ lines/cm$

Show that the second- and third-order spectra of white light produced b7fj yux-z5h 2adpyunx(,n f*/y a diffraction gratinu-7ny 52(*x ndzhf/f xp, ayujg always overlap. What wavelengths overlap exactly?

  When yellow sodium ligk1z)c2 bn;hdw;*i(t8q q tkmqht, $\lambda\;=\;$ 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 k0;2 w3:r j njqmqunk2pattern is viewed on a screen 2.5 m from the gratqun22kqn0w ;rm3 : kjjing. The incident light beam consists of two wavelengths, $\lambda_1\;=\; 4.6\times10^{ -7}\;m$ and $\lambda_2\;=\; 6.5\times10^{ -7}\;m$. Calculate the linear distance between the first-order bright fringes of these two wavelengths on the screen.    m

What is the index of refraction of a clear material if a minimum of 150 nm t/( yhblpic 0.jg lxfnr8.9)c ohickness of it, when laid on glass, is needed to reduce reflection to nearly zero when light of 600 nm is incident normally upon it? Do ynhy9)r08ipcl( jl g/f b.xco.ou have a choice for an answer?

  Monochromatic light of variable wavelength is incident norcs yxarh5rhp : ufs4f 58x.,g,mally on a thin sheet of plastic film in 5a: yr5 g, f8srp4huhs .,xcfxair. 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 thickne ux3f2o/ ovnxp,t);d1yx,,d1sc zs zy ss needed for an anti-reflective coating $(n=1.38)$ applied to a glass lens in order to eliminate
(a) blue (450 nm),    nm
(b) red (700 nm) reflections for light at normal incidence.    nm

  What is the minimum (non-zero)eh fh9or5 jd3n:6anb5 thickness for the air layer between two flat glass surfaces if the glass is to appear b fnjh95r3:n5d aohe6 dark when 640-nm light is incident normally?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the light transmitted through ak/ kixaa/x1.e thin film layered on a flat piece of glass. Draw a diagram, similar to Fig. 24–30 or 24–36, and describe the conditions required for maxima and minima. Consider all poss/xai kke/a x1.ible 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 refle,/-+1mylxmmcw;(yyp j *g n evy6pc 5ucting off a smooth lake is polapc 615-yep l*vn m,mmg;(+yywucyj/ x rized most strongly?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as tob)w7vkpi 8/cv reduce the intensity of the incident unpolarized light by an additional factor (after iv7bc8w vk /)pthe first Polaroid cuts it in half) of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light falls on two polarizer sheets whose trans+o(lk zj6hsw :2 d9wvi behz2-mission axes are at right angles. A third polarizer is pwbj2s6l d2h-vew:zho kz+ (9 ilaced 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 successiongsgw2d2ic)8 ;dkms /l 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.i:xh zaty6h wg;a*q1,e nh)- y0 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 rege*w-zy, na qa h: ;tiy6xhh1)d light of a He-Ne laser). Estimate the width of the beam when it reaches the Moon.    km

  A series of polarizers are eaa48l zzeyks0j7t izw)xc 88-vch 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 57dz)w ekhy955;c+hwot0tpl3nz xo j$(n=1.34)$ 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 s.hlnlu-3lne:4u/ eaphase with each other. They are located at lsene l4 .:-uhl nu/a3points $S_1$ 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 lightxs-wqv f .nttp:/1s1x containing two wavelengths, 420 nm and 650 nm, enters a silicate flint glass equilateral prism (Ffsxx1v spn ./:-t w1tqig. 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 a ;2gl ux0aw,ennd 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