Does Huygens’ principle apply cqet a xp9e+sg19x b(zh(hdh ,a/t:w .to sound waves? To water waves? Explain.

What is the evidence that light is enerrg27o p,bf6.8ujt ewsvtl )ujx0:b a (gy?

Why is light sometimes described as ra3g fz0pyx, +k.7pgk*5)zp iilkl2cux ys and sometimes as waves?

We can hear sounds around corners, but we ycb+ 1hu6vge1sd07ae cannot see around corners; yet both sound and light 1g e7e+b0va6s 1cuydhare waves. Explain the difference.

If Young’s double-slit experiment were submergwatswgi4y- ,( ed in water, how would the fringe pattern be -iwgsayw, t4( changed?

Monochromatic red light is incident on a double slit, and the interfemnwgv(k zd (f h+i5y,2rence pattern is viewed on a screen some distance away. Explain how the fringe pattern would change if the red light sodvz2 5 n+fy,w((imkghurce is replaced by a blue light source.

Two rays of light from the same source destructively interferef8d7 *wuu)s:ym o6c cq if their path lengths differ by howc d*:qw87sc uym6uf o) much?

Why was the observation of the double-slit interference pattern8hs t ,b2pih: jf;wko- more convincing evif- tpw2,s i h;hkjbo:8dence for the wave theory of light than the observation of diffraction?

Compare a double-slit experiment for sound wmby5 g:xsa h:0aves to that for light waves. Discuss the similarities and differences.a smgh:byx:05

Why doesn’t the light from the two heay2n*-w4y. x5io dwc3fc pn:kcdlights of a distant car produce an interfer4np cykn. -c2 d oww*f3yxci:5ence pattern?

Suppose white light fh f1m- *6jgtqr,2 glaysh4w4g alls on the two slits of Fig. 24–7, but one slit is covered by a red filter (700 nm) and the other by l ytwsj r4m-*g,6qa4gh21f gha blue filter (450 nm). Describe the pattern on the screen.

When white light passes through a flat piece of window glass, it : ;.h(i:i1peq*mqgiqyh hd7lmku 3 e1is not broken down into colors as it is by 31h*q(1pqi:emm h.;gd 7il q:ikuyeh a prism. Explain.

For both converging and diverging lenses, discuss how the focal ll e ,kz(eu/h6wength for red light differs from that for violet light ele, (6uzwh/k.

A ray of light is refracte0-ghj)sq n vg)d through three different materials (Fig. 24–55). Rank the materials according to their index of nhs0 qgg)-vj )refraction, least to greatest.

Hold one hand close to your ey l3,un)qnxxce/ k 9xi0e and focus on a distant light source through a narrow slit between two fingers. (Adjust your fingers to obtain the best pattern.) Describe the pattern that you s/9l0)n,kxxncuq i e3 xee.

What happens to the diffraction pattern of a single slit if the whole appar z kdkbgc cq6x .5d-9m5ib)hw*atus is immersed in (a) water, (b) a vacu* 6wh-zdk )db59q.kbc5 gm icxum, instead of in air.

For diffraction by a single slit, what is the effect ubz,97 tqzzt0 l e-im*of increasing (a) the slit width, and (b) the wavete im7l btzuq -90z*,zlength?

What is the difference;l( *oii7nf+fj7 p aax.p,jcv in 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, what is the advantage of (a) many slits, (b) clo n ,vqgsb)3j;osely spaced slitsnvo 3,gb jqs);?

White light strikes (a) a diffraction gratij;u:ab2 h i iaomygh/(29ya g9ng, and (b) a prism. A rainbow appears on a wall just below the direction of the horizontal a2 guigmj/ayb h 99 (oi:;a2hyincident beam in each case. What is the color of the top of the rainbow in each case? Explain.

For light consisting of wavelengths between 400 nm and 700 nm, incio3.jc /,ed.foo 5utk bdent normally on a diffraction grating, for what orders (if any) would there be overlap in the observed 3.ok fjb5 deo ,ctu/o.spectrum? Does your answer depend on the slit spacing?

Why are interference fringes noticeable only for ,y x89is8kqcu.u kr ;qu;eb ku+65 mbxa thin film like a soap bubble and not for a thick piecex+8yrxuke ukcqkub buqi.; ,6 89 m5;s of glass, say?

When a compact disk (CD) is held at an angle in white light, the reflected l1ftx v n5;y867kazfraight is a full spectrum (Fig. 24–56). Explain. What would you expect to see if montx1 nfz 7f8vaark6 ;y5ochromatic light was used?

Why are Newton’s ringsiej0ufsl j7 ;s jl92xujv;8 /b (Fig. 24–31) closer together farther from the center?

Some coated lenses appear 3uk nn/kzi6*k n-etl 0greenish yellow when seen by reflected light. What wavelengths do you suppose thnn3kkli60keu /zt-* ne coating is designed to transmit completely?

A drop of oil on a pond appears bright at its edges, wherjyq*6/k0xde3: fl azl e its thickness is much less than the wavelengths of visible light. What can a/y0z6ef:x* dqlj3k lyou say about the index of refraction of the oil?

What does polarization lm3p26 e4lk ac f:j5xqtell us about the nature of light?

Explain the advantage of polarized sunglasses over normal t3afa x,ws tlwt67 t(.rinted sunglasses.

How can you tell if a pair of sungw 9/g-gbp: 4 tamdwst8lasses is polarizing or not?

Two polarized sheets rotated at an angle of 9c2o3l( g o,c lcm57kcp0$^{\circ}\,$ 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 noxp) g5: bs5cdcvagtp 8sph45x fz5v71 atmosphere?

If the Earth’s atmosphere were 50 times denser than it is, wouldr- tfu-iyn oru7m7:-d sunlight still be whiter r-: i-7mtuuny- 7fdo, or would it be some other color?

  Monochromatic light falling on two slits 0.016 mm apart produces thedjzh-(nwfj7* fifth-order fringe -hdfz7*j j(w nat 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 atxsralt8 ), -ix 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 veryj 4lx5* :hinoi narrow slits 0.048 mm apart. Successive fringes on a screen 5.00 m away are 6.5 cm apart neari:hol4*xn ji5 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, wyrqb:t+,em4 l f5gh9 with a wavelength 656 nm, falls on two very narrow sliq+5m9g 4rhwtl,e:byfts 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 680 nm falls on two slits and produces an interference patte jh6xznm/i uqu tm(+9(rn in which the fourth-order fringe is 38 mm from the central fringe on a screen 2.0 / (z9 +6timmuq(h jxunm away. What is the separation of the two slits?    mm

  If 720-nm and 660-nm light passes through two slits 0.58 mm as x78fai ymv(qmtyn1s 1 b*5b/part, how far apart are the secq/ys7bbiy a5m(8x1mf1s*vt n ond-order fringes for these two wavelengths on a screen 1.0 m away?    mm

  In a double-slit experiment, it is found that blue light of wavelength 460 9fqem-uiv * u+g9u8 kpnm gives a second-order maximum at a certain location on the screen. What wavelength of v9qu+8gu mfp kie-u9*visible light would have a minimum at the same location?    nm

Water waves having parallel crests 2.5 cm apart pass through two ad94(hsjq(1co r( ylji/:ibnopenings 5.0 cm apart in a board. At a po bsj/94(nydi(h: lr1oaqcij(int 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 td4c 4y0lek5m f8q4 rhis placed in front of the lower slit in Fig. 24–7 so that the 8r fyt4l4h ke m54q0dctwo 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 maximum for light of wavelength4 g o1+z;gl5* 9jjx7-rpz 5aavjoiwew 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 5 jw+zargvep5;jl1 9jxz 4a7 *w-gooiis 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 5hr6,m5/)* bor d xwqmkwzk+m:0cbrv light. Find the distance between adjacent bright fringes on a screen 5.0 m from the sr5r+cdkqwzbmovr,x0wk hmb6m :) / * 5lits.    mm

  Light of wavelength 480 nm in 1 pkq u:rq1nmt5;rvr*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 plastimlbi;*k 4 amb.c (n=1.60) covers one slit of a double-slit apparatus illuminated by 640-nm light. The center point on the screen, instead of be*k bammbi4.l; ing a maximum, is dark. What is the (minimum) thickness of the plastic?    nm

  By what percent, approximately, does the speed ohkr0pitx0; -tw 1k6zzgp *+rhf red light (700 nm) exceed that of violet light (400 nm) in silicate;h1+gk pt-z xz0kirt 0pw*rh6 flint glass? (See Fig. 24–14.)    %

  A light beam strikes a 9m a-mvf+c09z 7 jsc5 jnklkz266oleppiece 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 light contain-/alnr,kwa97vf; +vfo t0 su sm+*yxo ing 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 sixkmmq -2; 9 ,y 7g.8,ropr tai:gcllrlit 0.0440 mm wide, what is the full angular width of the central diffractionyq2mmkl,ra:lt g,. i 87 -cgrx;9oirp peak?    $^{\circ}\,$

  Monochromatic light falls on a slit t hnlo6;rc 6wdksp3 g02/mt5 bnhat 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 (w2+g(du+ ) gcgkebqnc;md:b falls on a slit that is $ 3.20\times10^{ -3}\;mm$ wide. Estimate how far the first brightish diffraction fringe is from the strong central maximum if the screen is 10.0 m away.    m

  A single slit 1.0 mm wide is illuminated by 450 d;8 uf5fm gsduy6ld*enwe28(-nm light. What is the width of the central maximum (in cm6(wmg l8yu2efd*nfdd 8s 5;ue ) in the diffraction pattern on a screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm falls on a slit. If the angle b rc)ch,rjk(tl hi9*g3.xcx ga.s41oa etween the first bright fringes onxh)t(ir, o *hr3g cj1claax 94 skc..g either side of the central maximum is 32$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central diff5))qn a3gz xyxraction peak on a screen 2.30 m behind a 0.0348-mm-wide slit illuminated by 589- 3)gzn5xq )axynm light?    cm

  When blue light of wavelength 440 nm falls on a)i3- .fb pzxzn9 uhot5qk:g9d single slit, the first dark bands on either side of center are separated b)phdbz59x.nzu :-k9iqgo f 3t y 55.0$^{\circ}\,$. Determine the width of the slit.    $ \times10^{-7 }\;m$

  When violet light of wavelength 415 nm falls on a single slit, it creates a cent1 ;/ g6xh kb:d4tzaxsvral diffraction peak that is 9.20 cm wide on a scre46 d; xsah/gv:zxt1kben that is 2.55 m away. How wide is the slit?    mm

  If a slit diffracts 650-nm light eh:z jysj*(0t)kt5fqvq7vy bq ;zf1: 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 max:h eq)zs( :z5;0kf q*jt1fjtyv v qy7bimum for light of wavelength 420 nm?    cm

For a given wavelengtyufphs0y1x; r/t1i3 wb;2f x h,7etu sh $\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm light produce a second-orde*gaeth03 j -fmr maximum when falling on a gr- 3t0h *jmagefating 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 k g.ja0 ry5cisz;fp2 mx)i-8 ghave if the third-order occurs at an -kyjsmp.x 825 0gcfri z;i)a g18.0$^{\circ}\,$ 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 fao,)a7wnv8 c4 dmxb eur*yc6s +kf*lq, lling on a diffraction grating is observel*mr,6 o x+ ke8cunw4 7* vbyq),fcadsd at 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 h:vcdmb, tjn1d/4ujl4as $ 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 o4c yy*n1 l,p+ ( z*txlidw.iv(i8ldshn 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 zxo-h pu* h5u0with 6000 lines per cm is illumina- hzup0*hox 5uted with 633-nm laser light? Assume normal incidence.   

  Two (and only two) full spectral orders can be seen onk6ljv:iw5l1gx f,o d1 ( qpmc d*79jra either side of the central maximum when white light is sent through a diffrac1fv6, oplqj9*xd mjkl7rd(aiw 1g5c: tion grating. What is the maximum number of lines per cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containil;:2ewrkri9rdw0 m0ob0rz. r ng wavelengths from 410 nm to 750 nm falls on a grating withbrdzr ok : l0r;020wer.wir9m $8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which produces m1e k5u1zjy + 1qsfx3xconochromatic 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 line;8wn s+mdqp )ws are measured by a $9500-line/cm$ spectroscope at angles, on each side of center, of +26$^{\circ}\,$ 38$^\prime$,+41$^{\circ}\,$ 08$^\prime$ and -26$^{\circ}\,$48$^\prime$,-41$^{\circ}\,$ 19$^\prime$. What are the wavelengths?
$\lambda_{26.72^{\circ}}\;=\;$    nm
$\lambda_{41.23^{\circ}}\;=\;$    nm

  If a soap bubble is 120 nm thick, what wavev34ih3iqc q rv.r( um(length is most strongly reflected at the center of the outer surq4vqi. c3mri3vh((u rface when illuminated normally by white light? Assume that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the dark fringes oab1( iep4z:r )urt 1ain Example 24–8 if the glass plates are each 26.5 c1u()4eb opiaztr1 r: am long?    cm

  What is the smallest thickness of a soap film c0 j:ay/m:jet $(n\;=\;1.42)$ 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 greenisllhu8m b -vp+bu;h4 63gus xp-h yellow ($\lambda\;=\;570\;mm$ 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 a7kpmadk2) + gcnd 31 dark Newton’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 (Fig7ackmdk+p2 )g. 24–31). How much thicker is the center than the edges?    $\mu m$

  A fine metal foil separates one end of td- (yrbpeo3 n(wo pieces of optically flat glass, as in Fig. 24–33. When light of wavelength 670 nm is pn3((o-rb deyincident normally, 28 dark lines are observed (with one at each end). How thick is the foil?    $\mu m$

  How thick (minimum) shouldtu4 tz1o ;u6yu the air layer be between two flat glass surfaces if the glass is to appear bright when 450-n6u o t14t;uuyzm light is incident normally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, suspected of being a stolen qiquw2e/-/ 5 ec sv)scku4p.z 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 lm4e2unkxq 9,-dhig1l $(n=1.36)$ 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 appgz orzw 3/b5b/aratus (Fig. 24–31) is immersed in a liquid, the diameter of the eighth dark ring decreases from 2.92 cm to 2.48 cm. Whatr/3/ bz5w bgoz is the refractive index of the liquid?   

  What is the wavelength of the light entering an interferometer if 644 pnt dv997z 35e1zokp ibright fringes are counted when the movable mirro1o5zi dtk9ep9pz37 nv r moves 0.225 mm?    nm

  A micrometer is connected to the movable mirror ofj1)y .qt5og qk 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 thicknes gkqq o.)1y5jts of the foil? The wavelength of light used is 589 nm.    $\mu m$

  How far must the mirror lb+ h)d3 3ezh/mwh, ius5b ksf 4:lyxy1 zil77$M_1$ 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 a sm+f l+1hz1x)ov 0aq drxall 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 waveleng+0ra1oxxhd+z) vlf q1th of 610 nm. Calculate the index of refraction of the gas, assuming that the interferometer is in vacuum. $n_{gas}$

  

  Two polarizers are orecamw,; .y1e.e s0ad ns+tb.wiented at 65$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s angleonp s,c.muf()0n8 uvs for an air–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle fortok ndu9h,h-a3f 9-9zt*boxc a diamond submerged in water if the light is hitting the diamonfx dh3ub a zho*-9tt9o,cn9-k d $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the ligh:ijrs+d3k:;tfy2ld; nq a6ah t passing through them is a maximum. At what angle should one ofsdnj3+d6l: y;;r qi2:fta kah them be placed so that the intensity is subsequently reduced by half?    $^{\circ}\,$

  At what angle should the axes 5,a ))wrt:auui kp2 ruof two Polaroids be placed so as to reduce the intensity of the incident unpou5kr 2r: u),iw)puaa tlarized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are oriented at1 mkw/,8bjd,2,8 wbd 7pzho, suuvytd 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 orienteot*a2t ;gg7us d 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 surface of water for lp4k0d xam1nffn-te 4iov f/ ;2ight cmd-nveff1k4np2o i/0f t x;4aoming 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, eac qvk537yoebe,ap a+v: h of whose aey,pqv: oa ev7b+a 3k5xis makes a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength r. x(svj8g(j7ox9fl33wm2 fgu81hsslk a9 uq $ 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 mou7xlce,( a6z dnpf1gr(rr(*n e ntains or airplanes can interfere with the dirnzcf7*a n1d( 6grel( (p ex,rrect 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 sourceeilq:.r 2 y3zbs passes through a diffraction grating with r.yb:qe 32iz l$ 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 mmb ./ v4pil:vk-3gv vrn 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.v/4rng.-v:bv vi3 p lk What is the wavelength of the unknown light? $\lambda_2$    nm

A radio station operating at 102.1 MHz broadcasts from t43q/r;0 zf;cqszb ,5mo n/hrv7kc dbwwo identical antennae 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, perpendicula z7/45kqmcbwrf/v r b0n ,d;;hoqs zc3r 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 wids7c/pcvy2 a zf)2e/ eie, and blows a whistle of frequency 750 Hz. Ignoring refl 2f)ze vi 27e/p/ccaysections, 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 2:sw4k oce khu,8:iccsingle slit of width D at a 30$^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain begi651o/mft* mh0fxz metle have a series of parallel lines across them. When normally incident 460-nm light is reflected mx t/m51 oih6mzg0 ff*from the wing, the wing appears bright when viewed at an angle of 51$^{\circ}\,$. How far apart are the lines?    nm

  How many lines per centimeter must a grating have if there is to be ngx1 +rm13)fsxoja:a1obi 7 yjo second-order spectrum for any visibl1imaj7s+3 ax)r11 ox: ygjfboe wavelength?   $ lines/cm$

Show that the second-:rb6kda+qh6 su59 cxo and third-order spectra of white light produced by a diffraction grating always:9u o6h 5+6qxdrsk bac overlap. What wavelengths overlap exactly?

  When yellow sodium lighttqxdv/b(ns42 l yl95 87it lr7j,ecao , $\lambda\;=\;$ falls on a diffraction grating, its first-order peak on a screen 60.0 cm away falls 3.32 cm from the central peak. Another source produces a line 3.71 cm from the central peak. What is the wavelength of the new source? How many $lines/cm$ are on the grating?
   nm
  $ lines/cm$

  Light is incident on a diffraction grating with and the pattern is viewed on a9u 5ig/r saa+kh4k4d y screen 2.5 m f5r hs+kdau944yagk/i rom 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 material if a minimum e k / ccm+8tlg:n.. s.qw)yu,qv cexn,9 o9mhtof 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 it? Do you haveuto qvgh.e,t:cx nwe)c.,l.+m9/ ckm sq9 y8n a choice for an answer?

  Monochromatic light of variable wavelength is incident normally on a thin sh-dj a dy/x)x(kked+yf9h8d-c eet of plastic film in air. The reflected light is a min -h-d(afxdexcd9 j8yk /)+k dyimum 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 thicknes0zoi :i(l 3)ajup wcb l1xzo429xkhw6s 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 the air la; eqan konj9aj*n7 69frl/ne *yer between two flat glass surfaces if the glass is to appear dark when 640-nm light is incident normanae 9fqnn9 arken*oj/ * ;6lj7lly?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the light; z*teu- mw v0bk-e0q3m5bfcn transmitted through a 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 abqenk fct0umezbm;- -3w*v05 nd 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 smoot w1va,1qapm b3h lake is polarized most strongl3pmabw 1,q av1y?    $^{\circ}\,$

  At what angle should the axes i /1n(es 5feh78flqksf)spp tn29k gdo 16h7aof two Polaroids be placed so as to reduce the intensity of the incident unpolarized light by an additional factor (afts 72nsea fp k8ql617n)59 deghf/1o htkpif( ser 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 tran (t13scj hg.ggsmission axes are at right angles. A third p31c( sg gghj.tolarizer 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 succession with thj*r0t fy+ jw5m4d0ndox, s*ja eir 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 sliapn 7g-cq f*q3 k7/6o(uicepwt of width 1.0 cm and is pointed at the Moon, which is a p( pw/gcuqi3aq6 7*co-nfe7k pproximately 380,000 km from the Earth. Assume the laser emits waves of wavelength 630 nm (the red light of a He-Ne laser). Estimate the width of the beam when it reaches the Moon.    km

  A series of polarizers tesxud5c 6b-4-q a +wybcfa13hll 63s are 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 1piy ,(ymcodj;ri s-s ,g(p- bpu.nl/$(n=1.34)$ 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 waves iw+8(xs qzzk 2f8:hc /wxbki z8s1dj 9rn phase with each other. They are located at pointkix8 j 2wz8+c8zdk x wsq r(f:h/1b9szs $S_1$ 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, 42b wqh:h,4jz) )jcdzd -0 nm and 650 nm, enters a silicate flint glass cqj4dzd - hjbz):,w)hequilateral 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 surface ah1qem 8xxm sq+ ad*--end 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