Does Huygens’ principle apply to sound waves? To water waves? Explainn; 8jogda1kqrzt ob w8gq 206*.

What is the evidence that lie c4rq: 04w:z+by8pz1uyzcgr ght is energy?

Why is light sometimes describy1dj 2ox6gl d(ed as rays and sometimes as waves?

We can hear sounds around corners, but we cannot see around corneswr7 8 ql;k2airs; yet both sound and light are waves. Explain th7i sq2ka8;lw re difference.

If Young’s double-slit experiment were submerged in wate8df6 xp6v(txt r, how would the fringe pfvd(8px 6t6 txattern be changed?

Monochromatic red light is incident on a double slit, an; hyvc)breh7e)0s 6ker5 t9vg d the interference pattern is viewed on a screen some distance away. Explain how the fringe pattern would change if the red light source is replbe6e;khgy)9cr t)70vvesh 5 raced by a blue light source.

Two rays of light from the same source destructively inter gmtru(gnp6k981h d eedoy/)w 0l)a b0fere if their path lengths differ by how muw )9tpg( ryl no8 de60ku0a) g/d1hbmech?

Why was the observation of the double-s7 ;i/e uz/ ps/ixja/h5 ch8mhblit interference pattern more convincing evidence for the was5/7/pehua /iic/;xb j z h8hmve theory of light than the observation of diffraction?

Compare a double-slit experiment for sound waves tqha oqorvax 36g8-k.v), *cdto that for light waves. Discuss the similaritiesdkaq,3xo*ov)v6 r q.8a tcgh- and differences.

Why doesn’t the light from the two headlights ofcn c*u*yjr r42 ,fu5 syljk9-e;4oy is a distant car produce an interference patteruco- s5ulc,* 4reyn2 ys4kif 9j *j;ryn?

Suppose white light falls on the two slits of Fig. 24–7, but one slit is covern 5bfbnh5 +.iged by a red filter (7bbgn55f.h+ n i00 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 windo8a0j b 6ss4 .r(thqx2mnx(qgbw glass, it is not broken down into colors as it isxq4tas rb0 gjq 2(nx.ms(6b8h by a prism. Explain.

For both converging and diverging lenses, di0lj c8s6e l6b :vru/jgscuss how the focal length for red light differs from guresv0:j8cb6 6lj/l that for violet light.

A ray of light is ref leob+r2nsyt(8ipr .-12ctnqracted through three different materials (Fig. 24–55). Rank the materials according to their index of refract2tnsynelp+ i(- .2crb1 8 rqotion, least to greatest.

Hold one hand close to your eye and focus on a distant lig e9zjt *ex2+xdht source through a narrow slit between two fingers. (Adjust your fingers to obtain the best pattern.2 exzt+9dex*j) Describe the pattern that you see.

What happens to the diffraction pattern of a single slit if the whol8 g .5lxvj) 9qlcc-yxhe apparatus is immersed in (a) water, (b) a vallg xj .9-v5)q8x ccyhcuum, instead of in air.

For diffraction by a single slit, what is the effect of increasing (a) the* pb-y ;v22eyu4 u ,zo,iiz(scwd0vlg slit width, and (b) the wavez2 yv0pe,y4s* zc -u2io,vu (bg dil;wlength?

What is the difference in th jkfewd*)bmfk27in 3+ e 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 advantagfqy er4h4 * d )jmf.-d(imj:hdw oc6m+e of (a) many slits, (b) closely spaced d6*-4d fide rqjmh mmc fw .:+()yo4jhslits?

White light strikes (a) a difff mbrenzub7r(l28ikr (tg 78 *raction grating, and (b) a prism. A rainbow appears on a wall just below the direction of the horizontal incident beamgfr (ni zbe*r t(88u l7r2kbm7 in each case. What is the color of the top of the rainbow in each case? Explain.

For light consisting of wavelengths between )5 )t8-x+ts;n2*qrdhv,lxld wm qxxx400 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 x-ml8x ;,dh5swtxv)+2xq )l dx* qtrn on the slit spacing?

Why are interference fringes noticeable only for a thin film like yzy*y3(+rar7 /ftw toc3uel2cb(n i0 a soap bubble and not y zw*y+r3ct(bno2c/y7ue 3 0ta(lr if for a thick piece of glass, say?

When a compact disk f7d v;j*uya*rsd 1us5e1fn ) w(CD) is held at an angle in white light, the reflected light is a full spectrum (Fig. 24–56). Explain. What would y1j ys*d*;rf1ud7wn5 )eafu svou expect to see if monochromatic light was used?

Why are Newton’s rings (Fig. 24–31) c;a j:c) cwcpgf;): nieloser together farther from the center?

Some coated lenses appear greenish yellow when seen by reflected lie6 zxxsm+ c03yo6upo:ght. What wavelengths do you suppose the copx3ezux 0o+o66y:c s mating is designed to transmit completely?

A drop of oil on a pond appears bright at its edges, where its thickness is mucpd)gjaj *z q j1p8doi, cw 8e9x3i6hw,h less than the wavelengths oqjj w8,1,gzcdd8w)9 a 6heip3x jip*of visible light. What can you say about the index of refraction of the oil?

What does polarization tell us about t lzf4gq .w:c0f(n;v bihe nature of light?

Explain the advantage of polarized sungla1nlrld0vhsn v/n4hh u0r+j 41k : sw5vsses over normal tinted sunglasses.

How can you tell if a pair of sunglasses is polarizing or xt,t(.g4wvca se 5d+cnot?

Two polarized sheets rotated at an anj ;7qdl06 .3ddu6hx c-d ax8z bvpd,xvgle 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 n.;92xo y wftcsi(sfbo+)7 qdEarth had no atmosphere?

If the Earth’s atmosphm-x 3r dh zhwml2t9we*o3c8a.ere were 50 times denser than it is, would sunlight still be wloaxwemm z-h 3r2d c98. th*3white, or would it be some other color?

  Monochromatic light falling on two slits 0.016 mm apart produces tb 0dafg 0sfku) ew6t-*he fifth-order fringe at an 8.6sa fb0dg *wuf)t-e0k8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 610 nm lighn3cvakxh2 rd ms-7+ 0dt 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 0.048 mm apart. S) z upws4w 6 1:6eumkhdm6xpqn05x tc 4p+gzd0uccessive fringes on a screen 5.00 m a6 wt4 :x sz 0m5ppxzucd 6p0kh6wqn+ )dgem1u4way 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 fro g9n(tib;2vyjm a He-Ne laser, with a wavelength 656 nm, falls on two very narrow slits 0.060 mm apary;2(bv9gni jt t. 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 produce ;cbz0 *5lb(rnko-;y ivv lk7xs 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 tk (rcn7o0zb x k5vl b;v-l;*iyhe separation of the two slits?    mm

  If 720-nm and 660-nm light passes through two slits 0.58 mm apa 2rk y+*(ya nzctq+du,rt, how far apart are the second-order fringes for theseq+ dkr(*,y u2ctz+nay two wavelengths on a screen 1.0 m away?    mm

  In a double-slit experiment, it is found that blue light of wavelafau.kr )+v9ljbjska+px- y 3tc19s(ength 460 nm gives a second-order maximum at a certain location on the screen. What wavelength of visible light would have a minimum at the same locatio-1a9cxjsf ( 9saj+pa ukbl)yvrt+.3kn?    nm

Water waves having parallel crests 2.5 cm apart 93d n5 tej kkjqcfy-p gkzg 28z/*i:c)pass through two openings 5.0 cm apart in a board. At igntj2 kkekd3/8 -zp:9g5 c qyc f*)zja 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 f(i kgfgpp l1da04dy 46o(uj0q) fk*plower slit in Fig. 24–7 so that the two waves entygk4dg0fpf(d f6iq( p0lpu)k*1 o j4 aer 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-*co +i sqpfs zhjer+*3 +(cds8order maximum for light of wavelength 500 nm is located 12 mm from the 8+* *(s+zqc +srhpdcjs i3eof 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 illuminated by 544 nm light. Find ceks i3:bi0z rk;k 9a;o8jhmff1;jy*the distance betweerkk8kc*i; afjyjbzf3hoe 0m: ;; s1i9 n adjacent bright fringes on a screen 5.0 m from the slits.    mm

  Light of wavelength 480 nmo/cu gfgg7p*( in air falls on two slits $6.00 \times10^{-2 }\;mm$ apart. The slits are immersed in water, as is a viewing screen 40.0 cm away. How far apart are the fringes on the screen?    mm

  A very thin sheet of plastic (n=1.60) covers one slit of g7b a78vd, ay:8 zlri7of0mzma double-slit apparatus illuminated by 640-nm light. The center point on the screen, instegi78 :mbav077 yzmr doflaz8,ad of being a maximum, is dark. What is the (minimum) thickness of the plastic?    nm

  By what percent, approximately, does the speed of red light (700 nm) exce(*3 cly)4yb nx6vdfre-h bm,l ed that of violet le -rnh l,46mx(df )cyv3*ybblight (400 nm) in silicate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a + i+bofbd/pjk( )t:r; pz *nzipiece 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 likb 6cmpeqj *1u 8npe8(ght containing two wavelengths, $\lambda_1\;=\;450\;nm$ and $\lambda_2\;=\;650\;nm$, enters the silicate flint glass of an equilateral prism as shown in Fig. 24–58. At what angle does each beam leave the prism (give angle with normal to the face)?
$\theta_{d1}$    $^{\circ}\,$ from the normal
$\theta_{d2}$    $^{\circ}\,$ from the normal

  If 580-nm light falls on a slit 0.0440 mm wide, what is the full angular wb :g*rn 1.e wvwt(x*9r4ycsv aidth of the central diffracwwe9 ( a*cx*vsgrv.:4rb ty1n tion peak?    $^{\circ}\,$

  Monochromatic light falls on a slit that is*m6myavy,tgx 1q6t8 g $ 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 a2m9q/l -hbto k 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 x sslzdh7 v-8*light. What is the width of the central maximum (in cm) in the diff-hvds s 87*xlzraction pattern on a screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm falls on a sxrgp6 vfsb3,1q/as )ilit. If the angle between the first bright fringes on either si axqf, r/)vbp36gs1side 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 acu ,63e xd:o t dnt+u/4ir+bno 0.0348-mm-wide slit illuei+rnun+ 4 tcdbo:doux 6 3t/,minated by 589-nm light?    cm

  When blue light of wavelength 440 nm falls on a single slit, 4aaf*4gmusa4 the first dark bands on either side of center are separated4 *u4amaafg4s by 55.0$^{\circ}\,$. Determine the width of the slit.    $ \times10^{-7 }\;m$

  When violet light of wavelength nvn)*t p yt0q mixd3 tuh-;1.gdmc7p+415 nm falls on a single slit, it creates a central ddgc yt7m1nh.qt+v3xp;n- idu* mp)0tiffraction 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 that the diffraction maximum is l;q;z-uel -hx wq5rp:vzcl -84.0 cm wide on a screen 1- l-c :zp-rqzl;hql5xw8e v u;.50 m away, what will be the width of the diffraction maximum for light of wavelength 420 nm?    cm

For a given wavelengtr5 jy;qtd-ob ,mnz mk0/gx3 0h o:,wkoh $\lambda$, 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 maximum when fallinm7y9fi3.csgu kv x)4d g on a gi .fkumvd3sy7x9 g)c4rating 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 4zq:8jfm6uz g:-tqd:d6+zgzcxxo, u have if the third-order occurs at an :g6umd4xqj z c:q+8zo : gf-zx,z6udt18.0$^{\circ}\,$ 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 fa5/l +dv/eb2ixviwhbti8c6t )lling on a diffraction grating is observed at a 1 2dv)xiwvihe5+8 btl t6bc// i5.5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction grating has q ayxgi t/s6hk 3(v9:b$ 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 a *pvayo -o 8-hawit 8h($9700-line/cm$ 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 spec 8 3+qytxrc8gatral order that can be seen if a grating with 6000 lines per cm is illuminated t8r +cx8yg aq3with 633-nm laser light? Assume normal incidence.   

  Two (and only two) full spectral orders +o3cl s26yluacan be seen on either side of the central m ca+yu 36s2lolaximum when 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 yj bf) w.1l))h hvlk, pn8zcmkg54*fufrom 410 nm to 750 nm falls on a grating with18klvhj ,) g*cfm)lfkp4 z.n)5hwu yb $8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which pr6ff.3/ bit7q0j yrww t((wy zboduces 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 muvznx6 :t*d )d 1aq(dneasured 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 refl4 l,l6uw xo5 v+fxbcl4ected at the center of the outer surface when illuminated normally by white light? Ass ,ll5o cvx6 l4wbxfu4+ume that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the dark fringes in Example 24–8 if then 0et5 0z1ctrfvpcn; iw;w(, q glass plates are each 26.5 w(1e00tipnv qzr, 5cn;wtf; ccm long?    cm

  What is the smallest thickness of -( .u) a0rj6xevyei tea 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 yellowz2 xw-dzgfak-q/-:lhf:n, qlby 6m w9 ($\lambda\;=\;570\;mm$ 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 r2mv,dx )onnj vh 5 g6d,o4l3ebings (not counting the dark spot at the center) are observed when 550-nm light f v4moo)jh n, g b3nl5d26xv,edalls normally on a planoconvex lens resting on a flat glass surface (Fig. 24–31). How much thicker is the center than the edges?    $\mu m$

  A fine metal foil separates one end of two pieces of optically flat glas.:g +we:f d kduht/7wes, 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 is the foi w:guh t7 dw+kef./e:dl?    $\mu m$

  How thick (minimum) should the air layer be between two flat glassrqc1 g u6 d7znp:s93us surfaces if the glass is to appear bright when 450-nm light is incident nuzn sup3gs 7rd9 cq61:ormally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, suspected of beqw:9m tm1eutl1 ky5o6ing 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 alcoho2di2dtmk vhcf+cvr4*f +9n 3dws5f,q l $(n=1.36)$ 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 in a liquid, rxh1 -f6w-kutr.5+inoj 3g psthe diameter of the eighth dark ring decreases from 2.92 cm to 2.48 cm. What is the refractiverjo knfh.-ws6-5ru+t31 xp i g index of the liquid?   

  What is the wavelength of the light entering an interferometer if 644 r*gclysq8 f6 +d0z j-rbright frin0c +q8rfry g 6*js-zldges are counted when the movable mirror moves 0.225 mm?    nm

  A micrometer is conned5nk:1p l9x (sagg;gg cted to the movable mirror 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 wavelength of light used is 581 5gg :xgans (;kgp9ld9 nm.    $\mu m$

  How far must the mirror: nvvru4 ko;joze7g.4 $M_1$ 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) passej.o eqzvoir10i1nd 1)s 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 nr 1zid10eiojvq .)1othe index of refraction of the gas, assuming that the interferometer is in vacuum. $n_{gas}$

  

  Two polarizers are orien(( h 9ojn)gsmrted 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 airrs bd8 6 ib2/cnjl4,kn–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submerged in water if the light is n,li-f 0cz2dlhitting 2ncfz, 0ldi-l the diamond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the light passing throug8u eakmr8za;2 h them is a maximum. At what angaa 2em8u rz;k8le should one of them be placed so that the intensity is subsequently reduced by half?    $^{\circ}\,$

  At what angle should t o83zb2:-b qsidqi8q4 jvki;t he axes of two Polaroids be placed so as to reduce the intensitb4jqs-2:i;i3zd kq8 qvibt8oy of the incident unpolarized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are ori4yu+oqfc:u8jmav / l2- ehi*c ented at 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 fevj(m5(c eh6;wyms+ at 38.0$^{\circ}\,$ to one another. Light polarized at a 19.0$^{\circ}\,$ angle to each polarizer passes through both. What percent reduction in intensity takes place?    %

  What would Brewster’s angle be for reflections off the(psqw8h5 9tj lnw+,ii surface of water for light coming from beneath the su9i h8ijnp, (+tl5w wqsrface? 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 through five successive Polaroid sheets, each s*ylt 90hu)omp l/ d(kof whose uh kdlpso0l/yt()*9 maxis makes a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength gkc8 ov f+ x900 g:jccx rzys8m5m/nh79coly8$ 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 interfp-je t;( sk(goere with the direct signal from the ;j e( pk(ots-gstation.
(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 diffracto: gh;h.j xhwcxei8+8ion grating with 8g . c hwxh:xi;8ejho+$ 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. t vj5z:c4nx,e The screen is 1.70 m away. A second source of unknown wavelength produces its second-order fringe 1.33 mm closer to thet4 vec5z,n: jx 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 broadcan.)07hd.sl(ec t8k )zlyyydbf 9/gd ksts from two identical antennae at the same elevation but separated by an 8.0-m horizontal distance d, Fig. 24–60. Ayl 7 ltz b.d csd.ye) )0khkdf(n9g8/y 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 doorwa-rll* nlrk)2i,x mpg .y 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 playg,r )rmgp- n.* kllxi2lround outside the doorway.    $^{\circ}\,$ either side of the normal.

If parallel light falls on a single slit of widtp- ns5ec .nfx:h D at a 30$^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain beetle have a series of parallel linsm51 ms.km0y- ;y(fwy bq9xs nes across them. When normally incident 460-nm light is reflected from the wing, the wing appears bright when viewed at a0sy -1m sx (ms wbmfyq.5nky9;n 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 seco:omd*v*urk3m *v f r;vnd-order spectrum fom*;k*v ro fur*m:3d vvr any visible wavelength?   $ lines/cm$

Show that the second- and third-order spectra of white ligh9nzl/4oe) 9i9x w8e0 1oeuuqlp,npt e g; oox:t produced by a diffraction grating always overlap. What 4:8n9t,/i1 w9 epp9eqnzll0o oug )eoeu ;xxowavelengths overlap exactly?

  When yellow sodium light,z9qnvuk wgsv oxd5g0s gfh geza5:2a,3(,+z4 $\lambda\;=\;$ 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 patte 83rea h+u.unlr zgt nibj8)03rn is viewed on a screen 2.5 m frojh lu0t3 . nr8)8rngz ai3ub+em the grating. 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 materiwu okj)250ko jal 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 incident normally upon itw5o2 0jk jou)k? Do you have a choice for an answer?

  Monochromatic light of variable wavelength is inciden +ar*)a5 )r:yznc d3pgeo ja(x1i a(gkt normally on a thin sheet of plastic film in air. The ref(ie dxg :1n)3p cgzkayaajra+5 (* o)rlected 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 for an anti-refl9u x p7ab0z1zgwafg- 8ective 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 fj.* 8cff6qqjthe air layer between two flat glass 8qq*ff6.jcjf surfaces if the glass is to appear dark when 640-nm light is incident normally?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the light transmitted through a thinkk6iw:7)i.:sj jx( 4mfw wygg 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 possible valuex i6: . y7:4ikksfm jjgwwg(w)s 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 reflectingy.dq7k)t4j z q off a smooth lake is polarized most q.dqt7 4j zyk)strongly?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be pl r:;p oivcj: w0c ed8;d8+olmtaced so as to reduce the intensity of the incident unpolarized light by an additional factor (aft edt: cilp0m8 w+or;d:cv o8j;er the first Polaroid cuts it in half) of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light falls on two polarize. fgs)mcwl2o0-jnb70 r;zcq fr sheets whose transmission axes are at right angles. A third polarizer f qm of0cc7;b-rnz.swj g2l )0is placed between the first two so that its axis makes a 62$^{\circ}\,$ angle with the axis of the first polarizer.
(a) What fraction of the incident light intensity is transmitted?    $I_0$
(b) What if the third polarizer is in front of the other two?

Four polarizers are placed in sus v/s;jbaj)/co/ 1bgwccession 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 point(gvx5)qz9eu*w: ur e wed at the Moon, which is approximately 380,000 km from the Earth. Assume the laser emits waves of wavelength 630 nm (thee e95*vwrwuqxzu g):( 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 pl1* r4vdaaj47 brnm4bfaced 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 ck nzbj9 5jebcn t)s 07cbp88b(vj*z7$(n=1.34)$ 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-Mnft1e lply b0,+qba: ,Hz radio waves in phase with each other. They a:qab0l fly , e,t+b1npre 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 lig80icp)id q( 1arnc 4i47xavvtht containing two wavelengths, 420 nm and 650 nm, enters a silicate flint glass equilateral p4ci(ixca41tivn 7r q0d )a8vprism (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 m6lrpdvwbl48i 99fq 9has 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