Does Huygens’ principle apply to sounlx+;,4wy psm bss1e6kd waves? To water waves? Explain.

What is the evidence th aq(v9r6 fotkaz w:f9oaf:)x ;at light is energy?

Why is light sometimes descri yu14s8ny lol0j ww2 l;0a+*zhdykdj6bed as rays and sometimes as waves?

We can hear sounds around corners, but we cannot see arop7 ut: d t3au n3w03rxlo*ocob8x79cvund corners; yet both sound and light are wu nlto8d9v3x* 0upt7r 3ca :ow o3c7bxaves. Explain the difference.

If Young’s double-slit experiment wereeq xk99*xif m1 submerged in water, how would the fringe pattkx9ex9qim *1fern be changed?

Monochromatic red light is incident on a double slit, and the interference pafbwne*ng1c mg(5d; g: ttern is viewed on a screen some distance away. Explain how the fringe pattern would change if the red light source is replaced by a blue light sn gb dfg;c(g*me5:w n1ource.

Two rays of light from the same source destructively interfere if their path lbuv:.2 qc u4-o o)wqou(wis0uengths differ by how much?ou i0: uwq oso2cuubq)(v-.4w

Why was the observation of the double5hy7ur.a i,yl yye url2lzw**-*ms t--slit interference pattern more convincing evidence foryyu-a*t 2,l -lyr5.*m *yuriwe7ls zh the wave theory of light than the observation of diffraction?

Compare a double-slit ek4:q3/ 0e: u 9 rhmzszkk w9vbjt;bw5pxperiment for sound waves to that for light waves. Discuss the similarities and differ p:r zzw b0k:q349jkb;musvkw5et/h9 ences.

Why doesn’t the light from the two headpwc e*f:t;:t3 zui3ddlights of a distant car produce an interference pat3u:3c;:t*ieftw pzd dtern?

Suppose white light falls on the two slits of Fig. 24–7, but ow9wxr5fbhs3 x y;m;z)ne slit is covered by a red filter (700 nm) and the other by ;msxb w 35;rzy9)wfxha blue filter (450 nm). Describe the pattern on the screen.

When white light passes through a flat piece of window glass,l()l wrv fk;n. it is not broken d(lw .k);fnr vlown into colors as it is by a prism. Explain.

For both converging and diverging lenses, yyxn+bgjz -bg4 ,9vczr d 384mq2 jt.fqv4*midiscuss how the focal length for red light differs from that for violety,4. dgzjb4ij34m+2tn crvf mx*v 9gqby z-8 q light.

A ray of light is refracted through three different materials (Fig. 24–55). Rankal/7af;, vl eh5bk, jy the materials according to their index of refraction, ajyha b k7/elv,;,fl5least to greatest.

Hold one hand close to your eye -hy iu.fvun.lzsflh4c16mxx t i :v,x/t0 81m and focus on a distant light source through a narrow slit between two fingers. (Adjust your fingers to obtain the best pattern.) Describe the pattexml1i 8. 4fv:st n0fhzxu1.-6,liutxcvh /m yrn that you see.

What happens to the diffraction pattern of a single slit if theq+/(r/os)x huw pu t+x whole apparatus is immersed in (a) water, (b) a vacuum, instead of in airrtspwu) + uh x/q+x/o(.

For diffraction by a single sluqbt 9 * u18tt-6wczqwit, what is the effect of increasing (a) the slit width, and (b)69w t1tcuqu 8bt*wzq - the wavelength?

What is the difference in the interference patterns formed (a) by two slits dcev7se3 r o*;$^{-4}\;cm^2$ apart, (b) by a diffraction grating containing $10^4lines/cm$?

For a diffraction grating, what is the advantage of (a) many slits, (b) clz*(xg ps yzux0v*,nvaz1 4)aiosely *z1,iaa*v pz0zx)g(4 xvsnu yspaced slits?

White light strikes (a) a diffraction gratint+0z+ hl g ebig.d6zo/g, and (b) a prism. A rainbow appears on a wall just below the direction of the horizi bghz +6dt z+/.gel0oontal incident beam in each case. What is the color of the top of the rainbow in each case? Explain.

For light consisting of w xg+kk6awiv6 :avelengths between 400 nm and 700 nm, incident normally on a diffraction grating, for what orders6kwgxv+i:a k6 (if any) would there be overlap in the observed spectrum? Does your answer depend on the slit spacing?

Why are interference fringes noticeable only for a thin film like a soaqnw w1t/0zj2azodfmj76z 6z ;p bubble and not for a zw2 t z6/zqfj 1d7 w;m0n6jozathick piece of glass, say?

When a compact disk (CD) is3 i;n ( ej-bxzcrzl;x) held at an angle in white light, the reflected light is a full spectrum (Fig. 24–3zr-bjn ; e;lx)ixzc(56). Explain. What would you expect to see if monochromatic light was used?

Why are Newton’s rings (Fig. 24–31) cwk-sds+*(vpoy;n d/: wwos5.f z i* gjloser together farther from the center?

Some coated lenses appear greenish yellow when seen by reflected lig0e9ytjm ps )-yht. What wavelengths do you suppose the coating is designed to t)est 09j -pmyyransmit completely?

A drop of oil on a pond appears bright at its edges, where its thickness 2)47m: 7yxpn6hud, begzfg xgis much less thh4fp) gdeb:u7ny g,m 7 2xzxg6an the wavelengths of visible light. What can you say about the index of refraction of the oil?

What does polarization tell us about the natu vbs r.qm8zn,5re of light?

Explain the advantage of polariz(xyylm ;5bmt fxp,v vhw**00ged sunglasses over normal tinted sunglasses.

How can you tell if a pair of sunglasses is 709t hrddq(js 26i+9reesde rpolarizing or not?

Two polarized sheets roty(lucax*ty9r n5jz k7q .x;4sx41t bmated at an 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 Eam: atoqq.yte,9wc1 1,bmsf 7grth had no atmosphere?

If the Earth’s atmosphere were 50 times denser than it is, would sunlightf5xqiwnw.y0)grn6 j3p x: 7 ub still be white, oy:u) grwwf 0bi 73x5.nqnxpj6r would it be some other color?

  Monochromatic light falling on two nf;2f) nqd,s1pao -emslits 0.016 mm apart produces the fifth-order fringe at an 8.8a21nmfsfqe, on-;)dp $^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 610 nm light is observed db-ysq)r.e cx4a+q r) 0g/;vitpt0d0vkjv/k 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. Successive xl5c2s*t sty ivoqxf77t)erb8 1f0 s.fringes on a scre ib.v*txyl 8tf1s7sxt qrf 0s2)eco5 7en 5.00 m away are 6.5 cm apart near the center of the pattern. Determine the wavelength and frequency of the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of light from a He-Ne laser, with a wavelengthyyiujxn;6s*ct - ,j 0h2xssepn 1nx75 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 screenn ue stcn;s*xpy2j1s7-yx6,xh nj 0i 5 3.6 m away?    cm

  Light of wavelength 680 nm falls on //q4s: w+y doqn0szud two slits and 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 se / :nsz yd+04uwo/qqdsparation of the two slits?    mm

  If 720-nm and 660-nm light passes through,ls 35fkpbohss14ak ) two slits 0.58 mm apart, how far apart are the second-order fringes for these two 4o 5bp3 )1kslsah,kfswavelengths on a screen 1.0 m away?    mm

  In a double-slit experiment, it is found that blue light of wavelength 46g *bk d i/l4.pkh(tl72 thdm9j0 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 loghd9t(pl 4i k/tm . 7hjdbl2k*cation?    nm

Water waves having parallel crests 2.5 cm apart passrbau0j roow8-9ls.y 2s0vi5 y through 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 aywy -5robssu.2oij08 9r0vlwould there be little or no wave action?

Suppose a thin piece of glass issnnzs:f ft4 9m:u988xdmb2tu placed in front of the lower slit in Fig. 24–7 so that the two waves tsm nx2mf8 4t zsb:9nufd :89uenter 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 d5kaatc4ouvv 7yr)3m(5bm0s for light of wavelength 500 nm is located 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 mak5)ar5absv omcdvm3(u4 0 yt7 ximum of this light be located?    mm

  Two narrow slits separated by 1.0 mm are illuminated by 544 nm light. Find the fbn . +ce.oyb8distance between adjacent bright fringes e+y. bc obnf8.on a screen 5.0 m from the slits.    mm

  Light of wavelength 480 nm in air falltl ;2g u1it*dls 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 a double-sl2u n0l5skj8 yop (bw*rb6d: 5xddk2puit apparatus illuminated by 640-nm25 ( dbo05wkukspjdbpxu :ld82 *y6nr 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, does tht)tjpizuw4ov.ex u 41p+j )ll 2:1hhae speed of red light (700 nm) exceed that of violet light (400 nm) in silicate j oz)t1wv .14utejihx pllpa u4h+:2)flint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece of gl 1 xq scb)p:c9sk cu ,g3w20kl*,bfmynass 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 tmhl7xz2,5d(rdvc1t3 u 1 kp yxig 9(xewo 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 8uv,b8*grmy, 1l oecqangular width of lgrvymq,oe1 ,*bc88 uthe central diffraction peak?    $^{\circ}\,$

  Monochromatic light falls on a slit that is c*l(;oxn g pjef7k.k:$ 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 slh4tof- i)4 flyit 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 illumin6e uah*7nx7kx u 1fib*ated by 450-nm light. What is the width of the central maximum (in cm) in the diffractikx n7 ib*6ahxuefu*17on pattern on a screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm falls on a slit. If the angle between ta ;jzj vwd4p7gb-d4l ,f55ahn he first bright fringed4 h nza5-d7;blv agjf4jwp 5,s 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 2.30by9)k2 aqu nm83sfy h2 m behind a 0.0348-mm-wide slit illuminated by 589-nm lighthm)kyu32 2 sa8bny9q f?    cm

  When blue light of wavelength 440s,h +5u6xq vsf nm falls on a single slit, the first dark bands on eits6+qv u ,x5hfsher 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 falls on a single slitlq uc a: b43qbq./guu;, it creates a central diffraction peak that is 9.20 cm wide on a screen that is 2.55 m away. Hoquu.qglq/ ;u b:c4 ab3w wide is the slit?    mm

  If a slit diffracts 650-nm light soi5qjcoaybl is75ydz+s )qa 8y,i0d/3 that the diffraction maximum is 4.0 cm wide on a screen 1.50 m away, what will be the width of the diffraction maximum for ligsji iq0+i5ycz s/ldaq85 dy,)b oa7y3ht of wavelength 420 nm?    cm

For a given wavelengt *pb;s3+ phaiwhp4.7/bruvca e) jz ;eh $\lambda$, 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 fal aa.2k)+ejrglling on a grating a2 k.ra)egl j+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 have if the t)vt) 0seydjhw / z4xf4hird-order occurs at an 18. wh d/zexsy4jf)0)t v40$^{\circ}\,$ 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 ofmp5vqj+ l1w/b 589-nm light falling on a diffraction grating is observed at a 15.l j+5vpm1/qb w5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction grating 5 f(r rw/dqo1ebyn9+o 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 ;,isvh. yhgls:3s; lgon 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 orde*(yhujm2fw e+ r that can be seen if a grating with 6000 lines per c( *wmfu+hj2ey m is illuminated with 633-nm laser light? Assume normal incidence.   

  Two (and only two) full spectral orders can bf :ue7arr.tix// pfytl;y 7:pe seen on either side of the central maximum when white light is sent through a diffraction grating.lp.y7xttp : f;f/7u iry:ar/e 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 f.af8mh + 3 63,qasjpty g;ydyhalls on a grating with.p ;fyatmjd 6ayyhg3+s 3h8 ,q $8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which produces monq:l iw- clejmz6d2)/gei tt-.ochromatic 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 measured by ahzs*w.1cu.i+ 6 buzry8iud1 n $9500-line/cm$ 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, s o j 5-b7cd8o.rn:bqqwhat wavelength is most strongly reflected at the center of the outer surfd5c s-8qbn o7jb q:ro.ace 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 plates are eacy0 *nr 2c:/pabm 6q 2vr6dn7zc)+4sa jsgucldh 26.5 c*s2a6v/dzljs)c grn munb26r+:pq c4 dcya7 0m long?    cm

  What is the smallest thickness 2dhmpegs*p)l 7nx:.r/ meu 3 tof 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 yeg,m2ot ys*a2r/pm p5v llow ($\lambda\;=\;570\;mm$ 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 countrjkbi y 1)z sg(r-2;aeing the dark spot at the center) are observed when 550-n2zk ;er1ab( )syj gr-im light falls 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 ofkw5kg cvw,m 1; optically flat glass, as in Fig. 24–33. When light of wavelengthck5k 1;,wgmvw 670 nm is incident normally, 28 dark lines are observed (with one at each end). How thick is the foil?    $\mu m$

  How thick (minimum) should the air layer be betwau:zak4nved-4d+ rt so. +a8ceen two flat glass surfaces if the glass is to appear bright w8tua4s4+ nak: zdv a.ce-+d orhen 450-nm light is incident normally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, snd75l-36 wa m n4kwxmzuspected of being a stolen diamond $(n=2.42)$ is submerged in oil of refractive index 1.43 and illuminated by unpolarized light. It is found that the reflected light is completely polarized at an angle of 59$^{\circ}\,$. Is it diamond? ----待选择----yesno 

  A thin film of alcoho+ 1(vmgitsfo 2l $(n=1.36)$ 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 liqui x 9mo q+qom4y1c6zfzc,c+g. vd, the diameter of the eighth dark ring decreases from 2.92 cm to 2.48 cm. What is the rec mv91oqymf+oxzzc 4 +qg6.,c fractive index of the liquid?   

  What is the wavelength of t-sz*k 3wu4llc0(z)mfxb +eju he light entering an interferometer if 644 bright fringes are counted when the movable mirror moves 0.e3 (clsl jfkbz40-xw *m)u+zu225 mm?    nm

  A micrometer is connect ph8-. pxvw,woed to the movable mirror of an interferometer. When the micrometer is tightened down on a thin metal foil, thwh, xwpo v.p8-e 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 589 nm.    $\mu m$

  How far must the mirnj2ol* 66a pdjror $M_1$ 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) passes fejg e 3dq;q+0lfjft0.)-qdmthrough a small glass container containing aljt mgjf .e3 0f-e;0qddq q+f) cavity 1.30 cm deep. When a gas is allowed to slowly fill the container, a total of 236 dark fringes are counted to move past a reference line. The light used has a wavelength of 610 nm. Calculate the index of refraction of the gas, assuming that the interferometer is in vacuum. $n_{gas}$

  

  Two polarizers are orien1v s4dm3vu 9zlted at 65$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s angclaxald4 1 a8ibv3i 6)le for an air–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond 648cojwu kp7 4whrll.submerged in water if the light is hitting the u7lhj . pw lc6o4w8r4kdiamond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the light passin eg m(;1k7bt7;nid4oqby1n qz w2tn 3gg through them is a maximum. At what angle should one of tin1 z1kt g ynt2oq m4q3w(dnb;7g;be7hem 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 re*n( xnt3tr:x z1m) rzeduce the intens rr3z n) mxz(t1*ne:txity of the incident unpolarized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are orientedu x4aypv. 9pkd0.2l//f4mu xnaun:ez 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 oriel/bzs:c ,eb*b)a9+ ivmatj k1nted 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 bev 6usd; r(s,nlcq*9 oe for reflections off the surface of water for light cos ,(nvuc;*lo96 req sdming from 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 through five successive Polaroid sheets, each of w+,whc s +ozxov0.f j/those wh o+x.v/csjzt0 f,o+ axis makes a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength ov es0dp j9cmq m;fg5) p--tw)$ 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 reflectiurx5/ np dz(9ang from mountains or airplanes can interfere with the9uapn5r/ ( dzx direct signal from the station.
(a) What kind of interference will occur when 75-MHz television signals arrive at a receiver directly from a distant station, and are reflected from a nearby airplane 118 m directly above the receiver? Assume $\frac{1}{2}\;\lambda$ change in phase of the signal upon reflection.  ----待选择----constructivedestructive 
(b) What kind of interference will occur if the plane is 22 m closer to the receiver?  ----待选择----constructivedestructive 

  Red light from three separate sources passes through a diffraction 7a w1wr os3.p w(jtqy.grating with 3trw (qw.pwj . syao71$ 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 ah1 da qc2/t(guevj t;.dbk;y; part. 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 thankb; yvdd 2 e;tgjq. ;ta/uc1(h the 590-nm light. What is the wavelength of the unknown light? $\lambda_2$    nm

A radio station operating at 102.1 MHz broadcasts from two identical antaxj,say 9bpk8 6qj21d1 ;axj xennae at the same elevation but separated by an 8.0-m horizontal distance d, Fig. 24–60. A maximum signal is found along the midline, perpendicular to d at its midpoint and extending horizob1jj89s2k,axd;x1 y6ax aqpjntally 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 0bghx 7q /3n3qt.88 m wide, and blows a whistle of frequency 750 Hz. Ignoring reflections, estimate at what angle(s733hgb/xn qtq ) 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 l:.ehbjc1xii1 ;4n jw a single slit 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 across the*xx-jej / icu1m. When normally incident 460-nm light is reflected from the wing, the wing appears bright when cxe/ ijjux*-1 viewed at an angle of 51$^{\circ}\,$. How far apart are the lines?    nm

  How many lines per centimeter must a grating have if t eo2n m:f+w*:8 tr ll:e60r lnphe-twy(puus2here is to be no second-order spectrum foree 82tyt:lrfu ohnp-:le u ( :np2*w mls60w+r any visible wavelength?   $ lines/cm$

Show that the second-h *cb+ndu d9gp6w 7*wb and third-order spectra of white light produced by a diffractionc*w 6guwd7bbp9 nhd* + grating always overlap. What wavelengths overlap exactly?

  When yellow sodium light, b3e tnd 01us cfasf/99$\lambda\;=\;$ 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 3sq wq3hk;* ud(qkfx;on a screen 2.5 m from the grating. The incident light beam consists of two wavel3h*dqq ;(3;skufq k wxengths, $\lambda_1\;=\; 4.6\times10^{ -7}\;m$ 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 d2kb6q xo ab0f 0x8:pgmaterial 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 incidentab xqd806k: xg0f pbo2 normally upon it? Do you have a choice for an answer?

  Monochromatic light of variable wavelength is incident normath 8cp 8 +tv1utu.ca9zc. vem6lly on a thin sheet of plastic film in air. The reflected light is a mz.c.hu96a t8ue cv+t ct1 vm8pinimum 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 n8; q(dn( xcq*a1a cjoseeded for an anti-reflective coating $(n=1.38)$ applied to a glass lens in order to eliminate
(a) blue (450 nm),    nm
(b) red (700 nm) reflections for light at normal incidence.    nm

  What is the minimum (non-zero) thickness fo2vhlh*dip6l8 l2rujt.du f * ;r the air layer between two flat glass surfaces if the glass is to appear darhlut6pd*f *j2vu;rl2h8d i . lk when 640-nm light is incident normally?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the light transmittedoa rgcz sbpbjoebr06 1/*f 70q6x/ 7zm through a thin film layered on a flat piece of glass. Draw a diagram, similarc 0 z p7r sb6/0rbxzqgo7jb*m/oea16f 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 light reflecting off a smok( (deiro q0x7oth lake 7xo0qd (er(i kis polarized most strongly?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed h(toh9i /x2lsso as to reduce the intensity of the incident unpolarized light by an additional factor (after the first Polaroid cuts it in half)/( 2lo hs9ihxt of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light falls on two polae)ug7x;f rld)) w9w rprizer sheets whose transmission axes are at right angles. A third polarizer is placed between th);r f)pl)7 rw9u exwdge 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 succession with their axes vertical, at 33r3nf6r)i f- rn q* r:ffjga)e0$^{\circ}\,$ 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 s9 yhn v3ymf16cm and is pointed at the Moon, which is approximately 380,000 km from the Earth. Assume the laser emits wahvnm96f1y 3ys ves 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 an mv4 r4,cbv,ure each placed at a 10$^{\circ}\,$ interval from the previous polarizer. Unpolarized light is incident on this series of polarizers. How many polarizers does the light have to go through before it is $\frac{1}{4}$ of its original intensity?   

  A thin film of soap 3+mg(. pt)g8xkze1 piyv-g crp obj,xjc+6.x $(n=1.34)$ 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 radiat,g,yc nol ghes0f/m ro .hk;()ing 6.0-MHz radio waves in phase with each other. Theyc rm.f, )kog /s(ngoh0ley;,h are 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, 420 nm and 650 nm, enteub fz7s n459/sjm6a(vbdz 2crrs a silid9 /ba zsjru2sb76mc4vzf( 5ncate flint glass equilateral prism (Fig. 24–58).
(a) What is the angle between the two beams leaving the prism?    $^{\circ}\,$
(b) Repeat part (a) for a diffraction grating with    $^{\circ}\,$

  A Lucite planoconvex lens has one flat surf)ely 35dd t4.wp0m,i kpr ccj4.dyh6 sace 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