Does Huygens’ principy7s,x:ks/bn c03x up, qiimp/le apply to sound waves? To water waves? Explain.

What is the evidence that light isk ie bht1g8gh5+ 6qg.h energy?

Why is light sometimes desv6qui :loi;nyw* .0lvcribed as rays and sometimes as waves?

We can hear sounds aroz2ip1bc 8zokpt+6 hn+ und corners, but we cannot see around corners; yet both sound and light are waves. Explain thekci12nb+ 8h z op6zp+t difference.

If Young’s double-slit experiment were submerged in wate 8(oh6)wpam pyr, how would the fringe pattern be changehwp) ao8m(p y6d?

Monochromatic red light isqpg).ik a -ai+ 1 vvao7tq)p3r incident on a double slit, and the interference pattern is viewed r1i)) -ok.apqtq a3v7pai+v gon a screen some distance 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 destructivelye7samocp4uy o8+3;f(c e hy7d interfere if their path lengths differ by ho 7a 4us(o +c7ef hdo;y3ecm8pyw much?

Why was the observation of the double-slit interfetf /skf1qoj9d9kpc.4 rence pattern more convincing evidence for the wave theory of tffo jp.qd9ks/kc 941light than the observation of diffraction?

Compare a double-slit experiment for ;qm czxjji1n7pl(luy.0g8j.n j)g3y sound waves to that for light waves. Discuss the similarities and differences.c7y z;8(njnlujqyxi 1 jl3 .gjm0p)g.

Why doesn’t the ligh/n:c ww- qcj(pt from the two headlights of a distant car produce an interfe:pw/-c wqjnc( rence pattern?

Suppose white light falls on the two slits 8jhnj q/9quwg,6t ( bwof Fig. 24–7, but one slit is covered by a red ,ghtwu jq n8b/w9j6q(filter (700 nm) and the other by a blue filter (450 nm). Describe the pattern on the screen.

When white light passes through a flat piece of window glass, it is n.0i mdioqq dz*(hsa8:ov: 1cpot broken down in(mcqp*qoihoz1a vd: isd.80:to colors as it is by a prism. Explain.

For both converging and diverging lenses, discuss how the focal length for red ai* om7/f4 vot ft*lx7light differs from that for violet light m7* /xi4ft7toao fv*l.

A ray of light is refracs: ,o uom 8e)g ylj.d60sxgzt*ted through three different materials (Fig. 24–55). Rank the materials according to their index of refraction,yd6: o0szl u.so egg,)x*m8tj least to greatest.

Hold one hand close to your eye and focus on a d33pfyilmptl ;5 wi t n7os19+uistant light source through a narrow slit between two fingers. (Adjust your fingers film5ln p w+7s33y1tu9it o;p to obtain the best pattern.) Describe the pattern that you see.

What happens to the diffraction pattern of a single slit if the whole apparatg7szqpt4*u; o u, pm kd857rv . ph9j;nhtv2vfus is immersed in (a) water, (b) a vacuum, instead of in a p*ug ,7 o7;p8.dqv25;9ptjh4hu kntsvrzvfmir.

For diffraction by a single slit, what is the effect of increasing (a) the sli)c-qmf wa u oofc.vl(40dec 5)t width, and (b) the wavelf -u5c oo.clm0wfd 4( )v)qaceength?

What is the difference in the interference patterns formed (a) by two slitsx0tp 2/+eli qo $^{-4}\;cm^2$ apart, (b) by a diffraction grating containing $10^4lines/cm$?

For a diffraction grating, what is the advantage of (a) many slebb , *37oapa vw43wzjits, (b) closely spaced slitpbz7 vwo3ae 3bwa4*,js?

White light strikes (a) a diffraction grc 5 yeuy) bdegqm+b3bo0+n2r4y7a- okating, and (b) a prism. A rainbow appears on a2byymok7b+qy 5 c4r 3bgaudo+)-0nee 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? Explain.

For light consisting of wavelengths between 400 nm and 700 nm, incidena dg il,xkaoq9/ bz8:,t normally on a diffraction grating, for whadbi:/gl ,k axo9,q za8t orders (if any) would there be overlap in the observed spectrum? Does your answer depend on the slit spacing?

Why are interference friree; s-dr5 v)bnges noticeable only for a thin film like a soap bubble and not for a thick piece of glas;rv ebr5 es)-ds, say?

When a compact disk (CD) is held at an anh : :2,plozij2veuzsjeu)0+h o( p vb:gle in white light, the reflected light is a full spectrum ,i2j2el zzh+u:jvp) os v0 hu:op(eb:(Fig. 24–56). Explain. What would you expect to see if monochromatic light was used?

Why are Newton’s rings (Fig. 24–31) closer togetvq y yqf;)6;eiher farther from the center?

Some coated lenses appear greenish yellow when seen by yjj ci.b*5fn3 hn4yivr2;oa9reflected light. What wavelengths do byvi4 rcnhjj 2*.5;aifo 9y 3nyou suppose the coating is designed to transmit completely?

A drop of oil on a pond appears bright at its edges, where its thict ywpofp0v7k;d4q 5 s+kness is much less than the wavelengths of visible light. What can you say about tvytqpkp +f 4d 07w5s;ohe index of refraction of the oil?

What does polarization tell us about the naturz5o tkcjo2 i.2e of light?

Explain the advantage of polarw qbw /:lyb,rs8:4 uimuo76 dmized sunglasses over normal tinted sunglasses.

How can you tell if a pm/0trv z8.ofd air of sunglasses is polarizing or not?

Two polarized sheets rotated at an ak +d7k.cij:lo8 hc8jyngle 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 /0cx5antta92)xus lq the Earth had no atmosphere?

If the Earth’s atmosphere were 50 times denser than it is, would sunlig/6.s r)yzxm fmht still be white, or would it be sxz6y)mr/s m.f ome other color?

  Monochromatic light falling on twoehyzqfkr5dea+4d 0wq y): jy// qwy)6 slits 0.016 mm apart produces the fifth-order fringe atf)wry0q+yad4e z w5 q)yed:6/qjkh/y an 8.8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 610 nm li9fr e c/3s+.0pr5j wwbkrm2k ixs vy(.ght is observed at an angle of 18$^{\circ}\,$ when the light falls on two narrow slits. How far apart are the slits?    $\mu m$

  Monochromatic light falls on two very narrow slits 0.042f2zl1 s djlh58 mm apart. Successive fringes 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. dlzh212sljf5
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of light from a He-Ne laser, with a wavelength 656 n+g y.80o9dknhkxv g .hm, falls on two very narrow slits 0.060 mm apart. How far apart are the fringes in the centexd0 8g.kh ok+h9vny.g r of the pattern on a screen 3.6 m away?    cm

  Light of wavelength 680 nm falls on two slits and pror9 k/ lnhdbd. 4k/x 9ph/jps,tduces an interference pattern in which the fourth-order rksp txndhp kb94./,/ lj9dh/ fringe is 38 mm from the central fringe on a screen 2.0 m away. What is the separation of the two slits?    mm

  If 720-nm and 660-nm light passes through tw95x9sssze0s z :nk 64r,qdfbjo slits 0.58 mm apart, how far apart are the second-order fringes for t,6ze sq95 sjfx s0 9n4rz:bsdkhese two wavelengths on a screen 1.0 m away?    mm

  In a double-slit experiment, it is found thad5g e: /wp1jhzfw)w)t t blue light of wavelength 460 nm gives a sf / h)p5zww:g1w e)tjdecond-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 2.5 cm apart pass through two oyg)0:uksr1fng/3w 4x cn n*g) 2bdn bgpenings 5.0 cm apart in a board. At a point 2.0 m beyond the board,gw0g u2d)bxnf1*c) 3 ngynb4: rng/s k 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 the0ak:8n/kyyw8 wan0u* ihn8zu lower slit in Fig. 24–7 so that the two wavunkhwn8 8ay:w/n* u 800kizyaes 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 ligh a .0;mvg 2 r15qcjy(a6m)w5pwpuipv mt of wavelength 500 nm is locatedc yww .v(5 )agmjmi2u5pqarp;06v1 pm 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 located?    mm

  Two narrow slits separated by 1.0 mm are illuminao98fkwow*el-r3j z. pted by 544 nm light. Find the distance between adjacent bright fringes on a screen 5.0 rlzjwk -8fe3*w9.poom from the slits.    mm

  Light of wavelength 480 5:zh gs2c6m:2 whs8hs(iqlydnm 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 of3hpv fp( bt0l bdmz)92 plastic (n=1.60) covers 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 t 023 v b)f(zpmth9bpldhe (minimum) thickness of the plastic?    nm

  By what percent, approximately, does the speed of red ligt tm*di :6f*llee)o r-ht (700 nm) exceed that of violet light (4006l tr :ef) ldo*e*t-im nm) in silicate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece of glass fuws.qq fsi p *,x;.8hat 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 two wavelengtj* (d l+ hhigipq z)xx-7os9:ehs, $\lambda_1\;=\;450\;nm$ 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 full d;zt7s9 ttd b3angular width of the central diffraction pe tbtdsz7t9d ;3ak?    $^{\circ}\,$

  Monochromatic light falls on a slit thatfs xu;+z )vhu,ff5p4up xc,*r 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 / .af yq,orz*anm 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 t pzkop7i f vic9 ,x*co*s8/u3 3oskp,450-nm light. What is the width of the central o*3 / p,,78xkoiuziksc f9c3ps vop* tmaximum (in cm) in the diffraction pattern on a screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm falls on a slit. I* m+k1kg1u6m 3lq0cm +jdg xtlf the angle between the first bright fringes on either side mj+*g dk mg1ltx6 1lu3c+k0mqof the central maximum is 32$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central ;qa8g0i2 s)e o3uu *yh,cyvzs diffraction peak on a screen 2.30 m behind a 0.0348-mm-wide slit illuminated by 589-ngics he y,3yvus)*0auoq8 z 2;m light?    cm

  When blue light of wavelength 440 nmp *jnvcpa7 ;mm,qd5 r- falls on a single slit, the first dark bands on either ;jpv cd5*amq p-mnr 7,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 falszy*:zp h /xre k mrq 9;57aa,9j4a9t hqgolv)ls on a single slit, it creates a central diffraction pe5,hopmasjazke9:q;*z9rq tv9l7yx/)4 hgraak 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 that the diffradj *4mhbj dv*b pbe4p8o:a-ru7(u++up gg-iu ction maximum is 4.0 cm wide on a screen 1.50 m away, what will be th+d-eb puudh4(pgrbu+:jv4gmb8pu -ai * j*7 o e width of the diffraction maximum for light of wavelength 420 nm?    cm

For a given wavelengt0j7o a,smeqe0m zir q( 7w..rbh $\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm light pr nxp(st9wxdal4j 5. p*oduce a second-order maximum when falling on a grating whose slits arep*4n a(95d sxx.pjltw $1.45 \times10^{-3 }\;cm$ 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 occurw5b6ir41zhacoc;go . s at an cwg56i.a ozhc 1; 4rob18.0$^{\circ}\,$ 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 light5jtuj - w( r1 7i0aojjmk2cb*m falling on a diffraction grating is observed at a 15-(j or7bkiamu1m2jt jwc5*j0 .5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction grating:,jg u7uxue6p 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 o 3qw; k.ol/f abi3qbd:n 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 see4oed,c6gnsy7e , y -n3+uk4t u;+y ikhvbfq*en if a grating with 6000 lines per cm is illuminated with 633-nm laser light? Assume noru4noti4 fy*v-s;k+ un h7bc6 ,ed yk3gq,eey+ mal incidence.   

  Two (and only two) full spectral ord aeg-:9wbx5 ,z0w- a- sguandoers can be seen on either side of the central maximum wheaz-,- ue saa-5x bwo0gnw9: dgn white light is sent through a diffraction grating. What is the maximum number of lines per cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containing wavelengths from 410 nm to 750 nm falls on a gratin0wn ljpn 34mi1g with w l3n pjm1ni04$8500\;lines/cm$ 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 known wagndpjo-ecf .f(9 //2fuqg7sqvelength $\lambda\;=\;6.328\times10^{-7 }\;m$ 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 arbs3 x d -h(j;zt2rv-wue measured by a $9500-line/cm$ spectroscope at angles, on each side of center, of +26$^{\circ}\,$ 38$^\prime$,+41$^{\circ}\,$ 08$^\prime$ and -26$^{\circ}\,$48$^\prime$,-41$^{\circ}\,$ 19$^\prime$. What are the wavelengths?
$\lambda_{26.72^{\circ}}\;=\;$    nm
$\lambda_{41.23^{\circ}}\;=\;$    nm

  If a soap bubble is 120 nm thick, what wavelength is most strongly reflected acbn j8o,bgx/0 t theonj,bxcb/g 80 center 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 plai-xk 7 dgk:;-ljmij2btes are each 26.5 ckx: lk 7 gdjijm--i;2bm long?    cm

  What is the smallest thickness o)/ohnf 4dyb:e o0* fmbf 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 yjilffq w7h + nx*)0ko s76*pnlellow ($\lambda\;=\;570\;mm$ 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 (0 8umjun qsp o6ln:4m x:ghza3g)2emthe 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 center than tphm gmu)6(xen03 4jougaqns: m8lz 2:he edges?    $\mu m$

  A fine metal foil separates one end of two pieces of k.ssyb5fx z,4 em5s fre 704csoptically flat glass, as in Fig. 24–33. When light of wavelength 670 nm is incident normally, 28 dark lines are observed (with one at each end). How thick if5zs.04 xce75,s4k e fbrsmsy s the foil?    $\mu m$

  How thick (minimum) shoulidl r; 0xj h82h3; jxz(huw8 -sar3xsad the air layer be between two flat glass surfaces if the glas88;wh zsj(ixx0uhr32 a3 sh alj-;dxrs is 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 p3hw7 w)hkqbb s.9id6nh: q*9 s4uvnebeing 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 alcohot,9*al7fcyh4/k 8jqm:vz5cqm f0t msl $(n=1.36)$ 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 immersed v*hgxhf-u.(9 s8qvtyva4* gr in a liquid, the diameter ovhy 9gta.xs f*4g rqvhv* u(8-f 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 interferomeijk,1f + p9-xs6 gpabtter if 644 bright frin 9 -k1 ijga,pb6xtps+fges are counted when the movable mirror moves 0.225 mm?    nm

  A micrometer is connected to the movable mirror of a0lxh1 u1-w utfz hpsn120 oar;q9sje7l+)v cpn interferometer. When the micrometer is tightened down on a thin metal foil, the net number of bright fringes that move, compared to the emp;9 xtsll1 a )c-spjr1f2uqhn0+0z7 wvpo hu 1ety 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 fp4zz7f-c * re2e; /peahg* ji$M_1$ 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) passm +fp)a 2-oqpxes 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 umf2x) q-appo+sed 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 orien6fizh ehcb*w8k9rvq,fi n(0a );9o/jgom 7 v tted at 65$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s angle forbln9db h7 q(y5 an air–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submerg24 hsvf0w)ul sed in water if the light is hitting the diamonv)h2lws40 fsud $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so too c9c4 hup-t7hat the light passing through them is a maximum. At what angle should one of them be plaoc749 upc-othced so that the intensity is subsequently reduced by half?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as to reducz5hy/wadwy +: 7eg k+me the intensity of the incident unpolarized liwhw+/ykam y d5z+ 7g:eght to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are oriented at 40 jd,tiwn+e/lj:)t yz-$^{\circ}\,$ 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 38o4)cc10tb 9m ozdlr 5o.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 surface oy m(wdwrd *znx10,lzy9y0-zhf water for light coming frody 1d(hwnzr*,yx z-w9 z0m0lym beneath the surface? Compare to 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 througwhl40t,y, ,1aj4 fyc( ce:rapa)ex hd h five successive Polaroid sheets, each of whose axis makes a 4c1h lp,4r ,,0ywxe:(fye)t ja 4ach ad5$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength -9:wkmx7xu-ae q.wzuk/ci k ;$ 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 aiebpk4 wxtc)lo +r.8:urplanes can interfere with the direct sixotl ek p8+:b c.4)urwgnal 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 se01+ i x 3j;v-1)npomahlktifh parate sources passes through a diffraction grating with xl) 0itfa v mh3j1+pk;1n-hoi$ 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 sliv abn158rpc hrvk8;9xayy0 y7 ts 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 light. What is the wavey98cr 1 yn 5pay a;r7xkv0h8bvlength of the unknown light? $\lambda_2$    nm

A radio station operating at 102.1 MHz broadcasts from two identical antgxk9) se6xs sxiiizy r:hm-- /79 lhc)ennae at the same elevaci 6s:i 9le-rh9y7h- gxxm)ksi /)zxstion but separated by an 8.0-m horizontal distance d, Fig. 24–60. A maximum signal is found along the midline, perpendicular to d at its 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 outsid,c2 iwm*nm rp3/kj5qv9zth/ n e doorway 0.88 m wide, and blows a whistle of frequency 750 Hz. Ignoring reflections, estimate at what angle(s) it is not possible to hear the whistle clearly on the playgrou5*cw/j,9 vr m2kpq3t/hiz nnmnd outside the doorway.    $^{\circ}\,$ either side of the normal.

If parallel light falls on byb8 7eg5*a buuxj.3g:z6 wcy a single slit of width D at a 30$^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain beetle hbsaje9uix/4z* t54 b aave a series of parallel lines across them. When normally incident 460-nm light is refb/9 auz*bjit 4x4ase5lected 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 :vsw p;:y oxy 9ca . cvck0xv6/s(xb3lhave if there is to be no second-order spectrum for asoc6 aw : c:v vxvby(x/39 lp0;.xcskyny visible wavelength?   $ lines/cm$

Show that the second- and tnmgw x+uc1d8bfj,)v g8 x07r;dw axz5 hird-order spectra of white light produced by a diffraction gratin1x7;wvx 8 g,bnjd 0uxa+ zcm8w5) dfrgg always overlap. What wavelengths overlap exactly?

  When yellow sodium ligh(n*t c.ta a6p km)c:iit, $\lambda\;=\;$ 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 viewed on s7zn 5:vobrnx3fus74 a screen 2.5 m from the grating. The incident lighns7fvn r5uz 3:7 o4sbxt 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 materiap 6:1 x zq6ti6sd6klgyl if a minimum of 150 nm thickness of it, when laid on glass, is needed to reduce reflection to nearly zero when light of 600 nm is incxy:616gd6s t iq6plz kident normally upon it? Do you have a choice for an answer?

  Monochromatic light of variable wavelength is incident normald:p2t j+bbw-jn6 f;if ly on a thin sheet of plastic film in air. The reflected light is a minimumb+ jpnw-b;jf: ft62di 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-reflective coatb7qaxj n7( :vging $(n=1.38)$ 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 b 5 cpra4)bs.lhetween two flat glass surfaces if the glass is to appear dark when 640-nm light is ) cla5 p.r4sbhincident normally?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the light transmitted through a thin film layereh60p2p j)uv b36y yandd on a flat piece of glass. Drvy)ba0yp3h ju 62dn 6paw a diagram, similar to Fig. 24–30 or 24–36, 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 l sjt--o0lx/dc ight reflecting off a smooth lake is polarized most xjc0osd-t /l- strongly?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as to reduce the fa4p j/k+vd i(intensity of k pjafd4v(/ i+the incident unpolarized light by an additional factor (after the first Polaroid cuts it in half) of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light falls on two polarizer sheet fogh)2,5x:nva uffvl.)nvx 7ac9jf3s whose transmission axes are at right angles. A third polarizer is placed between the first two so that in f,.fv ln)cauxx )25a93o jvh:gf fv7ts 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 placew0q j)b 1zj8osd 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 th lw,gzsw9n)6 jrough a slit of width 1.0 cm and is pointed at the Moon, which is approximaz,s 6 9ngljww)tely 380,000 km from the Earth. Assume the laser emits waves of wavelength 630 nm (the red light of a He-Ne laser). Estimate the width of the beam when it reaches the Moon.    km

  A series of polarizers are each placed atjr4ahla phr/4sz5u.. 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 syg)jim,f0, m$(n=1.34)$ 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 go +6m0+i nn kdq0w;ro bjf9(ywaves in phase with each other. They jqi nf m6rg 00+d;b+w9yoo( nkare 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, 5yn71 8e-hbee5w hmb3 ci2 e4c*iwz(z ,tzj qr420 nm and 650 nm, enters a silicate flint glass equilateral prism (Fi4mb,(z hqc7e 8z z5n ri ebt3*5w-yiehejw12 cg. 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 j- f.orqc kgppw273dnp0 ;az5flat 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