Does Huygens’ principle apply to3 4,ttgg07a yqfxks3v sound waves? To water waves? Explain.

What is the evidence that light irzvul3g4.3sts: hog ;s energy?

Why is light sometimes descri)2xeq zaa)w 0.eu* raxbed as rays and sometimes as waves?

We can hear sounds around corners, but we cannb2pxn/j gs k+o vt(sp7 6+oa:mot see around corners; yet both sound and light are waves. Explain ga 2/b7:+j k 6ssom pptx(nov+the difference.

If Young’s double-slit experiment were submerged *3 vuen0p:oj; lyzb9min water, how would the fringe patternolujp0 yve n;3 :*mb9z be changed?

Monochromatic red lighwr2 ip gux;whca;uke)mw--36t is incident on a double slit, and the interference pattern is viewed on a screen some distance;- xupwkru h iwwg-;ea6m )c32 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 source0amd7j*ka y9 m destructively interfere if their path lengths d0kjmd7 9a* amyiffer by how much?

Why was the observation of the double-slit interference pattern morm)6ayrjzk) qmk; e5(ie convincing evidence for the wave thmeq ykr am))k(;56 jizeory of light than the observation of diffraction?

Compare a double-slit experiment f/* ezj79 .adesm;kcjt or sound waves to that for light waves. Discuss the similarities and differenct.jk/s9ed*;ae j z m7ces.

Why doesn’t the light from the two headlights of a distant car produce an in)fshu r* i*)w1 mwhj1nterferenw1* 1sji) u)mfw hr*nhce pattern?

Suppose white light falw546il gk s *qozu58h5/rx balls on the two slits of Fig. 24–7, but one slit is covered by a red filter (700 nm)5qbz6las5i85r/ wh4k o xl g*u 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 not +7/jfh4fq3je vbw a2o broken down into colors as it is by a prismvqo742/ba3e+ j fh fjw. Explain.

For both converging and . 0+y(wyjgdqwct(m n0diverging lenses, discuss how the focal length for red light differs from that+qn0jdg c0y mt(yw w(. for violet light.

A ray of light is refracted through three differentnid+ 1r 4thbrqgfg z:z,k *-x4z5y+yi materials (Fig. 24–55). Rank the materials according to their index of refraction, least to gr,gr4+-ty+:x f1q4 * d5nkhy z izgzbireatest.

Hold one hand close to your eye and focus on a distant light source through ag 9f e)1ec1 wvnf0hs9yq sn3,meiq y;( narrow slit between two fingers. (Adjust your fingers to obtain the best pattern.) Descr;0qvs39g symne 9 ) ,yif1ecen 1qh(wfibe the pattern that you see.

What happens to the diffraction pattern of a single slit if the whole appa3ct suc*+ 9fagratus is immersed in (a) water, (b) a vacuum, in3cc*sg +9fu atstead of in air.

For diffraction by a single slit, what is the effect of increasing (a) the sldfbe :uc j*82qg9 5r9r xzwk)iit width, and (b) th9zbu2je:drri8) f cgx kq95*we wavelength?

What is the difference in thx z13. 9ucbg urfcy:6ge interference patterns formed (a) by two slits $^{-4}\;cm^2$ apart, (b) by a diffraction grating containing $10^4lines/cm$?

For a diffraction grating, what is the advantage of (a) many slits, (b) cl-6glw, weuj792j9 iyma h3zngosely spaced slits3 2h,-7y9unwz9j wei gj6gmla?

White light strikes (a) a dz as40 jl dj3f+qa:/auiffraction grating, and (b) a prism. A rainbow appears on a wall just below the direction of the horizontal incident beam in each case. What is the color of the top/+l4 ad aasf:q j03juz of the rainbow in each case? Explain.

For light consisting of wav7.+5nnk kd+*zceogf n,j r fe6elengths between 400 nm and 700 nm, incident normally on a diffraction grnf*gr+k6. 5e,zf7+k cjeonnd ating, for what orders (if any) would there be overlap in the observed spectrum? Does your answer depend on the slit spacing?

Why are interference fringes not2y;wufg8rh*:k y v ry;iceable only for a thin film like a soap bubble and not for a wrh:vry 8y;;kyf2 *guthick piece of glass, say?

When a compact disk (CD) is held oed( yrwk2,zf l81qd+at an angle in white light, the reflected light is a full spectrum (Fig. 24–56). Explain. What would y(1k,yq2zr fw8l ddeo+ou expect to see if monochromatic light was used?

Why are Newton’s rings (Fig. 24–31) closer togethn i5qg1is.o:g2k,o - rai-rof er farther from the center?

Some coated lenses appear greenish yellow when seen by refla/rv,2,ppvz 5 l); zlcbr0n,bw 9 lvuaected light. What wavelengt, l50 ua)2vzv za lv;c/9r,p,wbplrb nhs do you suppose the coating is designed to transmit completely?

A drop of oil on a pond apfo*q sv fx0/g9pears bright at its edges, where its thickness is much lefo/v gq*xs9 f0ss than the wavelengths of visible light. What can you say about the index of refraction of the oil?

What does polarization te 4+plrsp lh4k.ll us about the nature of light?

Explain the advantage of polarized sunglasses over normal tinted sus5 jgcr9ao-*zh +5anrxce 7w94 -f1rt 2vxamsnglasses.

How can you tell if a pair o7*/ 23icmkm qxuwc )umf sunglasses is polarizing or not?

Two polarized sheets rotated at an angle o 3oz/i4mkb9 6yomdtb*f 90$^{\circ}\,$ with respect to each other will not let any light through. Three polarized sheets, each rotated at an angle of 45$^{\circ}\,$ with respect to each other, will let some light through. What will happen to unpolarized light if you align four polarized sheets, each rotated at an angle of 30$^{\circ}\,$ with respect to the one in front of it?

What would be the color of the sky if the Earth had nf5qz+ ;8oab+s73s6yehek 0qh jgcx h)o atmosphere?

If the Earth’s atmosphere were 50 times denser than it is, would sunlight sz(*duf9 cg2qvr* j(my .lq*dztill be white, or would it be some other c2um*rzfjyd.gzlq9*v(c(d q* olor?

  Monochromatic light falling on two slits 0.016 mm apart pro(3g994p-hhve bu)g5(kyn7j pi ko oxdduces the fifth-order fringe at7b-5o3y9ikxd)h(ppu n v kg9j(eho g 4 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 ar.j-o-k*sa w fi i c0(v4iw,emngle of 18$^{\circ}\,$ when the light falls on two narrow slits. How far apart are the slits?    $\mu m$

  Monochromatic light falls on twi 0x .p kpbauhxm7e,-+o very narrow slits 0.048 mm apart. Successive fringes on a screen 5.00 m away are 6.5 cm apart near the center of the pattern. Determine the wavx,0 ipu-e pmb ax.7h+kelength and frequency of the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of light from a He-Ne laser, with a wavelengti7ak:: jyia7qh 656 nm, falls on two i q7: i7aa:kjyvery narrow slits 0.060 mm apart. How far apart are the fringes in the center of the pattern on a screen 3.6 m away?    cm

  Light of wavelength j+ wn7un.zlwtq: fz2p,( 9vtv680 nm falls on two slits and produces an interference pattern in which the fourth-order fringe is 38 .wl ,(w 7n9zztvjp ftv:nq+ u2mm 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 throughx;ou: vx d5vvl5jx:m2 two slits 0.58 mm apart, how far apart are the second-order fringes for toju xdm;vvxxl5v5 2:: hese two wavelengths on a screen 1.0 m away?    mm

  In a double-slit experiment, it is found that blue light-w 3k.rt wnzkuf/+l)g of wavelength 460 nm gives a second-order maximum at a certain location on the screen. What wavewu n)gr+lk.t/fk3- wz length of visible light would have a minimum at the same location?    nm

Water waves having parallel crests 2.5 cm apart / 5dgstqrkg6e 46x uzt,s6zs) pass through two openings 5.0 cm apart in a board. At a point 2.0 m beyond) g zsu6zrxtt6q6,4kse/gs5d 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 low:s.v(lrgt hw1z( 4 d+g(evciw er slit in Fig. 24–7 so that the two z.(( l wgtv ehi4sdc1vg( +rw: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 8hofu:jzoicwoo60ta8z2 0;cyu . xq8, the third-order maximum 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 bo2jz:0 u xoufo 6ciyoaq8.h 80tz8;cw right 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 lightj (hx6pw7;ca ltavapw..5 9l s. Find the distance between adjacent bright fringes on a av7;6hcw lal (t5.j9sapx.wpscreen 5.0 m from the slits.    mm

  Light of wavelength 480 nm in air falls on tw2+*w84oc bx8gshzie f o 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 slityx* wy05 72c0it:hbnt uf he4x 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 the (minim0 4bh2c:t0e yy5n*w7hxxt i fuum) thickness of the plastic?    nm

  By what percent, approximately, does the speed of red light (700 nm) exceed thef9sl 5b70 sauat of violet light (400 nm) in silicate flint glassae095bus lf7s? (See Fig. 24–14.)    %

  A light beam strikes a piece of glass at a 61oex5(r wo0 ,eqz e+uq0.00$^{\circ}\,$ 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 ligh5 k5bb49i-l+h ha (;8 ocsx0gnrm gqpmt 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 widxy s48 snaov25e, what is the full angular width of the central diffraction panyx4o2s5 8 vseak?    $^{\circ}\,$

  Monochromatic light fall/6cmih+ig6 i p26cs bds on 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 slit 0. qgbl*lmu 9tthat is $ 3.20\times10^{ -3}\;mm$ wide. Estimate how far the first brightish diffraction fringe is from the strong central maximum if the screen is 10.0 m away.    m

  A single slit 1.0 mm wide is illuminated by 450-nm light. What in*km0*1kzq )mu1 wt) uuunlrh94i ; mps the width of the nu1mpw9qi nut04*km)lhu zkmu)* ;1 rcentral maximum (in cm) in the diffraction pattern on a screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm falls ezb8 lzjc8kl -vdeka-sq8:7h ,5il1 s on a slit. If the angle between the first bright fring sel7-8z1shce5k qa:8d-zvl8kbil j,es on either side of the central maximum is 32$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central dixss))dbqk u+ww ;qi+ (ffraction peak on a screen 2.30 m behind a 0.0348-mm-wide slit illuminated by 589-nm li w(sux kd+ ;sb)wq+)qight?    cm

  When blue light of wavelength 440 nm falls on a single slit, the firstby5*nug ,-wg s dark bands on either side of center are separated5unb*, sg-yw g by 55.0$^{\circ}\,$. Determine the width of the slit.    $ \times10^{-7 }\;m$

  When violet light of wavelength 415 h o z -yaxrk;lzl 6h5b3ha(t)8nm falls on a single slit, it creates a central diffraction peak that is 9.20 cm wide on a screen that is 2.55 m away. How wi tkrzlhh8a( -3)5l ha ;yz6xobde is the slit?    mm

  If a slit diffracts 650-nm light so that the diffractmct* n6 4:hmx.sg1n pjion maximum is 4.0 cm wide on a screen 1.50 m away, what will be the width of the diffract 1.nmj cx:ns4p6 tgh*mion maximum for light of wavelength 420 nm?    cm

For a given wavelengty;xsgszo;kaflp9kw8 3b 6 kp2(0* efbh $\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm ligbi1 gva t/7fw tdi4e-2u+ksya w+i3u 4ht produce a second-order maximum when falling on a grating whose slits aretiky+i2vaww tb7dfg4i4uue3 -s/+ 1 a $1.45 \times10^{-3 }\;cm$ 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 centimeso1x/ c2pxl 0lter does a grating have if the third-order occurs at an 18. lxl/s1 p0c2xo0$^{\circ}\,$ 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 di5e:,9ibif6b3 gkns up ffraction grating is observed at a 15.5, ubn539ks:iep 6big f$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction grating hx2*p vf( r0kvg 9k)fur1x/zbx as $ 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 onez,q, ec**1i zu ;fhsp a $9700-line/cm$ grating is revealed to contain three lines in the first-order spectrum at angles of 31.2$^{\circ}\,$, 36.4$^{\circ}\,$, and 47.5$^{\circ}\,$. What wavelengths are these?
$\lambda_{31.2}$    nm
$\lambda_{36.4}$    nm
$\lambda_{47.5}$    nm

  What is the highest spectral order that can be seen if a grating with 6000 lv z,,l8e9qb42rkvf boines per cm ib8r, l kbqz,2f94vove s illuminated with 633-nm laser light? Assume normal incidence.   

  Two (and only two) full spectral order n83vmotm,s:mn8i b1q s can be seen on either side of the central maximum when white light is sent through a diffraction grating. What is the maximum number1 nmi8 tqbvom,n: ms38 of lines per cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containing wavelengths f) hnt7m9rdvw6 rom 410 nm to 750 nm falls on a grating withhn9)d6 tmrw7 v $8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which produces monochkqxb sj i( /9fqt47z9nromatic 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 arerd:5n2 +hiant(ly q6j sk( ws5 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, whatawx6t mrae*:o bck w ,0v9,w*y wavelength is most strongly reflected at the center of the outer surface when illuminate wo 6 waev*,a9:c*,k mtryxb0wd 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 eachy gdiv.9 .xb6df,e:/s4hinr w t.dss6 26.54tvrg/s :6id.xdwd neyb.is fhs ,69. cm long?    cm

  What is the smallest thickness of a soapmr4*kq 9a9 i f5iw9gul 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 (+5 o9 vjsbscdxu ::b-r$\lambda\;=\;570\;mm$ 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 clo,q z8o+, u-kjm w/xxounting the dark spot at the center) are observed when 550-nm light falls normally on a planoconvex lens resting on a flat glass surface (Fig. 24–31). How much thicker is the centemokx qx+-uz,j8ol,w/ r than the edges?    $\mu m$

  A fine metal foil separates one e h q +vpo)lum;cr8zn6kff q2:1nd of two pieces of optically flat glass, as in Fig.2o p+1fzruch8;v q6k lfnq)m: 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 foil?    $\mu m$

  How thick (minimum) should thxjm/nutzwo63 1 1un5 me air layer be between two flat glass surfaces if the glass is to appear bright when 450-nm light is inc3/5m6 xmwzo1 ntj uu1nident normally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, suspected of being a stu,zt4h+m s/kz olen 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 alcoh9/-4mn )x(jx i scyx pc1fg5guol $(n=1.36)$ 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 (Figq(i a,mnrr/x 0. 24–31) is immersed in a liquid, the diameter of the eighth dark ring decrea mrx0nr(,qa /ises from 2.92 cm to 2.48 cm. What is the refractive index of the liquid?   

  What is the wavelength of wxx*j po9kf e5uu1h; 2the light entering an interferometer if 644 bright fringes are counted when tehxfj51uw92x * ku op;he movable mirror moves 0.225 mm?    nm

  A micrometer is connected to the movable mirror of oq* eis8a; 8-u*yay-epwq 2 gwan interferometer. When the micrometer is tightened down on a thin metal foil, the net number of bright fringes that move, compared to the empty micrometeq8ue*qe*iwyw -ap sa8 g2-yo;r, is 272. What is the thickness of the foil? The wavelength of light used is 589 nm.    $\mu m$

  How far must the mirzv 0xx6 1ejve*ror $M_1$ 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 through s nt4x0 3orzbqsrsi324/man3a small glass container containing a cavity 1.30 cm deep. When a gasn3 t 0isroa2s4b4ns3m3 x/qzr 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 oriv(3k- v-v ym/dsn khr1ented at 65$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s ah2 v dp-; o zx.x(/rvhzwm+hh3ngle for an air–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submerged in water ik 0pnmk/u ;*7iiv-sywf the light is hitting the diamok;ikin p0- /vsu 7m*wynd $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the light .j,.iws,3mmi z +kacr passing through them is a maximum. At what angle should one of them be placed so that the intensity is ms,rjk +.iciw3.zm,a subsequently reduced by half?    $^{\circ}\,$

  At what angle should the a y.2ij:rgu2b9 cniqes za e9ml8+hc3 :xes of two Polaroids be placed so as to reduce the intensity of the incident unpol9 lsqgjei2.3e9bcm28 ia un:zhy c r:+arized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are or5ev3* ;;m;o 0ixwtg, bqbxyk e; vod(riented 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 orientofg -e.p4rid5n2z,r,wyhi l39s0udw ed 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’st f*5) vfrd-ro angle be for reflections off the surface of water for light coming from beneath the surface? Compare to the angle for total internal reft)r*vrof -d f5lection, 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 pas-uk2atd uf8 pdyh :*,lses through five successive Polaroid sheets, each of whose axis makes af d*k yau,-phldu 28t: 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength tu, 97dpr dnb )gdnw0(t7 a7et$ 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 azn p125g je5 g6uxb3kgirplanes can interfere with the direct sign2g5b z65u3njg xpe1gkal 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 gratingvptu-k qak/+2): qbmn with qkbv)- : nuk2ptmq+/a$ 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. The s i,llqd0lpc9d4z r+. v+ibnk9 creen 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 wavelength of the unknown lightcd. k9l+in9q,0 z+l4r vd ilbp? $\lambda_2$    nm

A radio station operating at 102.1 MHz broadcasts from two nf7+4f0yfk 5/swa+ jpm9gzanidentical antennae at the same elevation but separated by an 8.0-m horizontal 7ff+za5g0m/n9a w jyfp 4k+sndistance 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 outside doorway 0.88 m wi 2g kncbkr6g/5de, and blows a whistle of f rcng6kk/2 b5grequency 750 Hz. Ignoring reflections, estimate at what angle(s) it is not possible to hear the whistle clearly on the playground outside the doorway.    $^{\circ}\,$ either side of the normal.

If parallel light falls on a single slitjmk23ltg1 8d 5 xz3t-haqx 3nm 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 them./:kl/,htxs im* y q9xe When normally incident 460-nm light is reflected from the wing, the wing appearltxqmk s /x:,ye9h/ *is bright when viewed at an angle of 51$^{\circ}\,$. How far apart are the lines?    nm

  How many lines per centimeter must a grating have ir(( 2 gobl98 agqwv1obf there is to be no second-order spectrum for any visible wavelength?(gqo9o g1alr8vw2 (b b   $ lines/cm$

Show that the second- and third-order spectra o raya4 0zdazcm -3gj;a,89idtf white light produced by a diffraction 8tadi;zc ,a4 m-gyaz03a9jdr grating always overlap. What wavelengths overlap exactly?

  When yellow sodium light+9*x s9gz tfecj*:g qutmqu.,, $\lambda\;=\;$ 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 viee3xnn/2l1b t) nbm ne+wed on a screen 2.5 m from the grating. The incident light beam consists of two wavelengt/ l n2eetm)+3b n1nxnbhs, $\lambda_1\;=\; 4.6\times10^{ -7}\;m$ and $\lambda_2\;=\; 6.5\times10^{ -7}\;m$. Calculate the linear distance between the first-order bright fringes of these two wavelengths on the screen.    m

What is the index of refraction of a clear material if a min4voe-o d. 5au s3/khedimum of 150 nm thickness of it, when laid on e-ads54 ou/.doehk v3glass, is needed to reduce reflection to nearly zero when light of 600 nm is incident normally upon it? Do you have a choice for an answer?

  Monochromatic light of variable wa,o*5 lxtoc b9mxjw*d 80v ex6z ,eilx)velength is incident normally on a thin sheet of plastic film in air. The reflected light isli wc v 6mt0)e,**zj,5l8xe bxoxo xd9 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 thic, w6;hcyd5x tt2fi,knkness needed for an anti-reflective coating $(n=1.38)$ applied to a glass lens in order to eliminate
(a) blue (450 nm),    nm
(b) red (700 nm) reflections for light at normal incidence.    nm

  What is the minimum (non-zero) thickness for thdy3 qzhgv*q 9p*;.ua we air layer between two flat glass surfaces if the glass is to appear dark whqdq9.pa*v;* g wuz3yhen 640-nm light is incident normally?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the light transmitted through j4*o rcra v00da thin film layered on a flat piece of glass. Draw a diagram, similar to Fig. 24–30 or 24–36, and describe the conditions required for maxima and minima. Consider all possible values of index of refraction. Discuss the relrv04dj r c*0oaative size of the minima compared to the maxima and to zero.
24-30
24-36

  At what angle above the horizon is te1e75cr h9ns5n,pcd the Sun when light reflecting off a smooth lake is polarized m t,55rn end7pech91 scost strongly?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be p6hk 0)d.e5zrojwgh( j i.ks0z laced so as to reduce the intensity of the incident unpolarized light by an additional faczhrzsk(wd6k h05.jo)jig0e . tor (after the first Polaroid cuts it in half) of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light falls on two pr05p/nz, e xpt,mn.xok tc)8lolarizer sheets whose transmission axes are at right anglestpc. nox zk, 5t 8)px,/rel0nm. A third polarizer is 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 successil k42;ov/q w/o1s8da6mcm 2xcob lby1on 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 sl , blq0omrz;6ait of width 1.0 cm and is pointed at the Moon, which is approximately 380,000 km from the Earth. Assume the laser emits waves of wavelength 630 nm (the red light of a He-Ne laser). Estimate the width oz60aqb;r m,l of the beam when it reaches the Moon.    km

  A series of polarizers a2 m :4cmgzj6iw9dt,4bi i y(bxre 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 7c :2;7n njpyw rdukb;$(n=1.34)$ 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 waah-(box z6;uh ves in phase with each other. They are locauh x- hz6;o(abted 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 65eusm q-zqdm bt5 5w,r7/oh.(i0 nm, enters a silicate flint glass equilateral prism (Fi5bd/.zq qr,7h( 5tme wmuoi-sg. 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-5pltdv8hmv7e-m -o bace 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