Does Huygens’ principle apply to sound waves? To water ont(b;dj 8)ciwaves? Explain.

What is the evidence thathza.t vz)2z l, light is energy?

Why is light sometim 8.gkpu r1s7nc.5 dzeves described as rays and sometimes as waves?

We can hear sounds around cornyvm ;n: ;hqo5lers, but we cannot see around corners; yet both sound and light are waves. Explainnq;h:5 y vlmo; the difference.

If Young’s double-slit experiment were s .9vxti g7-s1iq3l bzuubmerged in water, how would the fringe pattern be 9uil z7tb.qxgs1-v 3ichanged?

Monochromatic red light is incident on a double slit, and the interferen5jez0 6)gnxlvce pattern is viewed on a screen some distance away.0zv x) ljgne56 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 9mc githd59vw97n xp0v4q uf8source destructively interfere if their path lengths diffeum9 tn99vv 75qwh 8 c4fgi0pxdr by how much?

Why was the observatipw x: fr)os1a,on of the double-slit interference pattern more convincing evidenrwpf 1os:,)a xce for the wave theory of light than the observation of diffraction?

Compare a double-slit experiment for sotigyc0fd aq.g/q*1 1cund waves to that for light waves. Discuss the stcfi*c q qdgya 1/1.0gimilarities and differences.

Why doesn’t the light from the two headlights of a diweb :xx,7mh)astant car produce an interfea,x)bewh m7 x:rence pattern?

Suppose white light falls on the two slitp 8 ggx0pdn2w43uc vru7.pgh*s of Fig. 24–7, but one slit is covered by a red filter (700 nm) and the other by a blue filter (450 nm). Describe the pattern on the screen. 0uw 7vgx ngd*23puphcp r. 8g4

When white light passes through a flat piece of window 2is ff5:yq55e.j(ocg)xaxpi glass, it is not broken down into colors as itxfox scygap:) . f(25e5ij iq5 is by a prism. Explain.

For both converging and diverging lenses, discus t6l*iq0hfo 5t 1ihoh0d(g (cfs how the focal length for red light differs from that for violet fof* t51 h6qhhtci(lo00 gdi(light.

A ray of light is refracted through threedhd* kewf pya5lr,+eip1: 7z. different materials (Fig. 24–55). Rank the materials according to their index of refractioz k.p17+*w:dyal,e ihf 5 redpn, least to greatest.

Hold one hand close to your eye and focus on a distant lhs0zy6f i ;1yfight source through a narrow slit between two fingers. (Adjust your fingers to obtain the be;hfz6i10ys yf st pattern.) Describe the pattern that you see.

What happens to the dbg s7cf/5t8e k hw37xriffraction pattern of a single slit if the whole apparatus is immersed i8fskgwhx 5 t7e/3r7bc n (a) water, (b) a vacuum, instead of in air.

For diffraction by a sry9:grbfs0p - vaa.(ck 5qk3ringle slit, what is the effect of increasing (a) the slit width 0g 9krp3rs:a-a5b qc(rvyfk., and (b) the wavelength?

What is the difference in7 *l2y n-7trrjecw y0n 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, *hw)pb3n) q 7wfj/svnmq17c te-vv7t what is the advantage of (a) many slits, (b) closely s)b7v q fhvm)t3/7p v wj*1tnc-qe7swn paced slits?

White light strikes (a) a diffraction grating, and (b) a prism. A u,l8/9ohvxlcuzq2lj zy-4 f;rainbow appears on a wall just below the direction of the horizontal incident beam in each case. What iqc /u2,-hz9; ljy8xzlo4ul fv s the color of the top of the rainbow in each case? Explain.

For light consisting of wavelengths between 400 nm and 71a .4jkaph. x q)ehqd700 nm, incident normally on a diffraction grating, for what orders (if any) wo4hapj7)qa dxq1k .h.euld 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 soap bubb 5 a9/t2ccds0./m zivjfeq:tzle and not for a thi /icte z29ca.jv/0: tqsm5dfzck piece of glass, say?

When a compact disk (CD) is held at an yt q-n8 hn5+kasgtuiej,(a9 4 angle in white light, the reflected light is a 4n,gie-st h 8 9qkat(5+nayujfull spectrum (Fig. 24–56). Explain. What would you expect to see if monochromatic light was used?

Why are Newton’s rings (Fig. 24–31) closer together farther from the ceo/9+ h2wn2gppd1j 1fijrib jep+ (y 63scax/dnter?

Some coated lenses appear greenish yellow when seen by;o*yxqe f(m j,*ifba8g8e9xp reflected light. What wavexxi f ym (*j8bgp8q*e,9fo ;aelengths do you suppose the coating is designed to transmit completely?

A drop of oil on a pond appears bright at its edges, whqc+jr3 yt. wg5ere its thickness is much less than the wavelengths of visible light. What can yourj.yg5+tq 3wc say about the index of refraction of the oil?

What does polarization tell us about the na3dms.lwl fu ;(ture of light?

Explain the advantage of polariw ()c.ylv o 7vmc ;u5thcu36vized sunglasses over normal tinted sunglasses.

How can you tell if a pair of sunglasses is polarizi6)5,wg g +*9 xs mhmavsm(qdsbng or not?

Two polarized sheets rotated at an angeh.vig0lu/y t i 3s/,cle 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 ifbr ,2lvgw,. 5 ba hyb,rj5lgh( the Earth had no atmosphere?

If the Earth’s atmosphere werzkp;xrlp-j;n4bvgfr +wl ng 3 4* id1:e 50 times denser than it is, would sunlight still be white, or would it be some other color?4zd1rwg *l+gi :;nrnfx j4-klp3;pvb

  Monochromatic light falling on two slits dm3h0k)9 d :tzitl5kz0.016 mm apart produces the fifth-order fringel9 zthkkd0) z: i35dmt at an 8.8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 610 nm light is observed at an ang 3;pa+hh reht)le 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 apartx /,vq0( uwpdn. Successive fringes on a screen 5.00 m away are 6.5 cm apart near the center of the patter/ dw 0(vuqxp,nn. Determine the wavelength and frequency of the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of light from a He-Ne laser, with a wavelength 656 nm, falls onnf cl k;.fe7k0ov- dj6 two very narrow slits 0.060 mm apart. How far apart are the fringes in the k0c7 k6; fnv.-le dfojcenter of the pattern on a screen 3.6 m away?    cm

  Light of wavelength 680 nm falls on two slits and produces an interference2kkx)3we a3iipcfbo)ul -5 ;g 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 tw -obla kk;up3x5ei f)3 2gic)wo slits?    mm

  If 720-nm and 660-nm light passes through u.cmndz4a .ag0f5+ dnh * pu(ytwo slits 0.58 mm apart, how far apart are the second-order fringes for these two wavelengths on a screen 1.uzp u+*m ( n ydn0ca.ad5h4g.f0 m away?    mm

  In a double-slit experiment, it is found that blue ligrla08;sb54w0lxd ng dht of wavelength 460 nm gives a sec xnd sra8l;g 40d0wbl5ond-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 throu;3poez84fkp 9g mb3 augh 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 therag4 p3k8;mpeb3ouzf 9e be little or no wave action?

Suppose a thin piece of glass is placed in front of the lower slit ini g3k(:o:v swo Fig. 24–7 so that the owskiv o:3(:g 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 max*tc2 59u+njieq v8lfzimum 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 projec+qnf*8lj zt ivu95e2cted 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 ar:8sdkq 2jon0q7 j o,5 fbv3name illuminated by 544 nm light. Find the distance between adjacent bsoq5a,v fo3nbqjd m7:82 jkn0right fringes on a screen 5.0 m from the slits.    mm

  Light of wavelength 480 nm in air falls oxwat;6 i g1 xpg9w1of5n 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-slit apparathbe-:1p tlccdj4s 0f9 us illuc h bct 0-ed9l4fjs:p1minated 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, does the speed of red f favv.y3:v2/gikaw.1( fnj klight (700 nm) exceed that of violet light (400 nm) in silicate f/3vg f1. ik nj .ak(wfv:fva2ylint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece of glass at a 60.g-h)fvwuyt /000$^{\circ}\,$ 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 y(-l7;cbp97cok silr 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 slite,axoqody6 gq -pu2 7( 0.0440 mm wide, what is the full angular width of the central diffuq7 y,6 qa 2d-expo(ograction peak?    $^{\circ}\,$

  Monochromatic light falls on a.wnj6:l3o yb a slit 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 suqmx t5/.zsr3lit 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 wi*x6xnn514u o7v6 wg wyqo4vomde is illuminated by 450-nm light. What is the width of the central maximum (in cm) in the diffraction pattern on a screen 5.0 m a4mgw6oony4 716 xvv nu5*wxqoway?    cm

  Monochromatic light of wavelength 653 nm falls on a slit. If the angle boy :yl1 871o*gu4t u:dtnh xabetween the first bright fringes on either sideax 8yth:7*4l n11u :g odotbuy 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 o+b6k9s9,4/ vbeh)fb rbsgd wjb/c m).0348-mm-wide slit illuminated by 58/w+hrb k)be4c vg69/d9)j, sosbfb bm9-nm light?    cm

  When blue light of wavelength 440 nm falls on a single slit, the first ,dhpfyj0x4t30 :oyk sdark bands on either side of center tks0y pdyjx,34f h:0oare separated by 55.0$^{\circ}\,$. Determine the width of the slit.    $ \times10^{-7 }\;m$

  When violet light of wavelength 415 nm ,;,;n cgv9 hnqfauff5falls on a single slit, it creates a central da nv;;n9f,ch5fq f ,ugiffraction 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 j* jtya7*97cusc 77xk mv8i tc650-nm light so 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 light of wavelength 420 n a*77mi7v xucyj879c tsc*k tjm?    cm

For a given waveleng3:dnqh o ue4i0rw*l ,ss8nr/tth $\lambda$, 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 falling onl15 i2:t54oqhl hm e/zcqg)lm a gratingih5el5ql m)/z oc g41hqtm l2: 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 h)/wmjq;2dny o,cww 7zave if the third-order occurs at an 1, ww;wjmonyq 72 d/c)z8.0$^{\circ}\,$ 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 diffraction gdk 1lsu 58ieo)rating is observed at5ei8luos d1 k) a 15.5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction grating k07varj9 noxkzrnh1:o8r 9r. k sw9.q 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 onlqflve bmv d3 -1y1vjc* 2o(ehe/g ; 4iy*te3z 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 +sbx:l +nd qc/seen if a grating with 6000 lines per cnl/cs+ :x b+dqm is illuminated with 633-nm laser light? Assume normal incidence.   

  Two (and only two) full spectral orderw:vw1b 89wa5 mg *nmjme6uq:m. jen-ps can be seen on either side of the central maximum when white light .j19 bmmewe uv6wq*-wm:amp5jn 8 ng: 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 75(r vmq dhh+::fdw2t 2geiw6 ol1th1.o0 nm falls on a grating with lv+t1 odgfrq1i hwe 2:whd: 2 mh6to.($8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which produces monochromatic light 4ze5*8vf xsbk 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 pdkuwom.ku- omlw 3+k 0ah ou8,*b8)(i/oldvare 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 nynzw /-j 2)toam thick, what wavelength is most strongly reflected at the center of the outer surface when illuminated normally by white light? a-2z)oj/yntw Assume that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the dark fringes in Ex.f lecgi.,u-v ample 24–8 if the glass plates are each 26.5 cm long-uf g..,lviec?    cm

  What is the smallest 3hdn- hdo .7ksthickness of a soap film $(n\;=\;1.42)$ that would appear black if illuminated with 480-nm light? Assume there is air on both sides of the soap film. $t_min$    nm

  A lens appears greenish yellow .-yfjl-3 oq5kpzu w qotv.ev:i2 dov 4)u+c8 o($\lambda\;=\;570\;mm$ 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 Newtou dy1bq6x j:bqq)fkoh:)(u j*s/il )xn’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 tui:1*bh:) syd q) uo qb(x lj6xq)kjf/hicker is the center than the edges?    $\mu m$

  A fine metal foil separates one end of two pieces of optica9mm+ k/ p+, qysupo7dqb ced,6lly 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)p9ums+ /mqb cy+p 67q,kd edo,. How thick is the foil?    $\mu m$

  How thick (minimum) should the air layer be betwemqn u7 6+9zxi)h zx/yaen two flat glass surfaces if the glass is to appear bright when 450-nm light is incident no6/)+9iuzmxzh ya 7qnxrmally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, suspected of being a3(d sw*( rzvmk 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 alcoha 8 (e/blzery( /ybk+thw-dug /b ;ly3ol $(n=1.36)$ 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. 24dy,enc*s g8l .–31) is immersed in a liquid, the diameter of the eighth dark ringeycs*gl. d,n8 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 interferometer if 644 b5)lc o.v qpmb6)q1hwyright fringes are counted when the movable mirror moves 0. h l.)oqw5)qmp 6vcy1b225 mm?    nm

  A micrometer is connected to the movable mirror ofambvcou -ni r)btu q/ti/9c*qa7ak((l ;mv, . an interferometer. When the micrometer is tightened down on a thin metal foil, the net number of bright fringes that move, compared to nqbv9.tklui*/) /;cauaot (7av mc b,-q mi(rthe 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 mirrorag *f4.eq qllc6x:+6srhd+pe $M_1$ 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 thro+c l3kqc s88ks(gt7s zugh a small glass cont k(cgs s7ck83qtsz8+l ainer containing a cavity 1.30 cm deep. When a gas is allowed to slowly fill the container, a total of 236 dark fringes are counted to move past a reference line. The light used has a wavelength of 610 nm. Calculate the index of refraction of the gas, assuming that the interferometer is in vacuum. $n_{gas}$

  

  Two polarizers are oriented phec-gsde+2 1 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 air–glas+1jwy w : h-g1kwxg8sts $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submerged in water if the light is qdirh ,33ynf2d1sg6whitting t3r d s3f6hgyqd2 1iw,nhe diamond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the light passing through them is a xqdr/; h phi/1maximum. At what angle should //;rdihp h q1xone of them be placed so that the intensity is subsequently reduced by half?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be plac /ylewu 8a+ bu(m*v7xrd8:yised so as to reduce the intensity of the incx7aeuv: rw m8 8liydb*y (/u+sident unpolarized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are oriented isq8eehk8+s k( q2sw :xv8vp*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 p,c5j/e*ix ey.n2mkx 6wpc, iat 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 r u.kjf a r4 +6ft9kjrgl0i(*ube 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 frku0*a9j rff (gl6 kujt+4r. irom 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 P;d b-f w1)lo )jhyv77 pey+ijrolaroid sheets, each of whose axis makes a lep7+-ojyrdhi;bw71) y )jfv45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength 0kholf/22de w;7rgaw2qp vg2 $ 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 airplan 2 *+hj+ 48zyrlrjsl(f9s vpj.hn)bsqes can interfere with the direct signal from the st j8n2v(+r*4syf qbrj)+lh.zp ss9jlhation.
(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 throughf;kfz;0fdx ; p a diffraction grating with pz;kf 0 fdx;f;$ 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 narr9li li8/byxl*kd. 0yc ow 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 light. What is th y 0c8.x y/*lkii9dblle wavelength of the unknown light? $\lambda_2$    nm

A radio station operating at 102.1 MHz broadcasts from two identicax*5 ah:xx7t fzl antennae at the same elevation but7 5*xz htfxx:a 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 outkvpb6f x gp40):tgei;ulsr fd ,rr+*.side 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 playground outside the do+kg 4,*sl rdrrf;ufp t6gei.b:vpx)0orway.    $^{\circ}\,$ either side of the normal.

If parallel light falls on a ah uq3hrg d8-,single slit of width D at a 30$^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain beetle have a00aw5/nwz aywg8 e0la series of parallel lines across them. When normalgyaa lww ez 0a/0w8n50ly incident 460-nm light is 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 c87sxeir. * dp:8 dypxientimeter must a grating have if there is to be no second-order spectr x87iy8spr.di:pd e *xum for any visible wavelength?   $ lines/cm$

Show that the second- and third-order spectra of white light produced by a diffrzfvo., i oc7amto2h 7,action grating al7, tomia fo2ov c7.hz,ways overlap. What wavelengths overlap exactly?

  When yellow sodium ligpq obanu*(yx;ydn)qxc,z;q3z; 0 y)fht, $\lambda\;=\;$ 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 diffrwqke; 0mpz;0x nc1r4laction grating with and the pattern is viewed on a screen 2.5ln0 qme rzwp;; ck140x m from 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 .gof)u1 qvjewhy. l2pb. (/ll a clear material if a minimum of 150 nm thickness of it, when laid on glass, is needed to reduce reflection t. pl g.beoyul1h wl)/(q vj2f.o nearly zero when light of 600 nm is incident normally upon it? Do you have a choice for an answer?

  Monochromatic light of var abfnv(7s5*w :not1v ciable wavelength is incident normally on a thin sheet of plastic film i1n:wb (o*tncvf v75sa n air. 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 thickness needede- xb)cc c9 rtdk;alt8fu 57k0 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-z wh inar1dr(7:ero) thickness for the air layer between two flat glass surfaces if the (d : 71whrirnaglass 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 th9- 9e6)fjvnyq 1byqppin 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 values of index of refraction. Discuss the relative size of the jf qp9yq6 v9p yb)n1-eminima compared to the maxima and to zero.
24-30
24-36

  At what angle above the horizon is the Sun when light reflecting ofx i1sfmb. (p6mf a smooth lake is polarized most pmm6(x . bsfi1strongly?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as t 8t5dr r*uvo ;2nzc0fdo reduce the intensity ofrtn2cv*u5f zor 8d0 ;d 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 sheets whose transmission axes are at p7e,nc 1oy l u:6s jtuwt;:dd6zvfp)4 right angles. A third polarizer is placed between the first two so that vddzof4cwe: y;6t,67u s tunp1j :pl)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 wi51yvg;u/*;rp g/yd o likz0(z n(z gdith their axes vertical, at 30$^{\circ}\,$ to the vertical, at 60$^{\circ}\,$ to the vertical, and at 90° to the vertical.
(a) Calculate what fraction of the incident unpolarized light is transmitted by the four polarizers.
(b) Can the transmitted light be decreased by removing one of the polarizers? If so, which one?
(c) Can the transmitted light intensity be extinguished by removing polarizers? If so, which one(s)?

  A laser beam passes through a slit of width 1.0 cm and is pointed at the Moon, w(8i qoit/ / pez,w)bqlhich is approximately 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 M/(q)ioqbpzi8 e,wlt/ oon.    km

  A series of polarizers are each2 0csnytc up(*xh5i o( 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 +;p7/ k4gpomfxt7e jq $(n=1.34)$ 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 6.0o,9xecd )b d4b/jiyp2-MHz radio waves in phase with each other. They are locjcxdy p,b2/b)4ed9 ioated 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 lm;8au d4:d2 k0. vlykbmgn) lnm and 650 nm, enters a silicate flint glass equilateral prism (Fil)mv40nuy dalb82g:.kdk ml;g. 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 s-p9cl aaggiff)ho ( 3)5p3pqxurface 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