Does Huygens’ principle apply to sounh3dsrl y u +q19:p1mwod waves? To water waves? Explain.

What is the evidence that light is energy?ff5.dnz(49 i6 ksppkrrgiv8:

Why is light sometimes desz,su ps 5e3h 38mgfig/d a:a-mcribed as rays and sometimes as waves?

We can hear sounds around cor srt4ibq)ur+ 3yeq0cae1l 8h8xr; m5m3s,uchners, but we cannot see around corners; yet both sound and light are wa+ea8i)8 3lys t bcs5 0qhr,43;mr r hxqcuue1mves. Explain the difference.

If Young’s double-slit experiment were submergiu, /nwf*2hd gptf/b ,ed in water, how would the fringe patt ihpgf*//t,w, ub2d nfern be changed?

Monochromatic red light is incident on a double slit, and the interference pai+soxuh(y 39sttern is viewed 9us(o3h +xsyi on a screen some distance 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 source destructively interfere if theiro,*-w qlomys.i-tj :p4f qkuv107d io path lengths o1.ui*70jlp vsq:-km4q fiy-owt do,differ by how much?

Why was the observation of the double-spd+xkg3** fpj0o1l (lq bgy:dlit interference pattern more convincing evidence for the wave theory of light than the obsq fg k+l1bo g*dj0ly:(3xp pd*ervation of diffraction?

Compare a double-slit experiment for sound waves to that for light waves. Di:g ffg0eh ,ck-scuss the simi:gf ,-kfgehc0larities and differences.

Why doesn’t the light from the two headlights of a8 , gcve6(ys poze08jh distant car produce an interference ev 6j8,zposceg0(hy 8 pattern?

Suppose white light falls on the two slits of Fig. 24–7, but one slik .ptlhgugg)3 nt6 l18b8ai k0t is covered by a red filter (700 nm) and the other by a blue filter (450 nm). Describei.k)8 1kbla nl0ut6g3pg hg8t the pattern on the screen.

When white light passes through a flat pieceaskwy )fl(7m-b d,3 lu of window glass, it is not broken down intoa 7bdl3-,l uyw( )skfm colors as it is by a prism. Explain.

For both converging and diverging lenses, discussfr uw1l5tk5bqvow7 .q f( t r;d77en-d how the focal length for red light differs fr7o-.5 fqqb 5d(rkue7 r1wtvwt lndf;7om that for violet light.

A ray of light is refn 4vmcax.gv0 w,e*b+tracted through three different materials (Fig. 24–55). Rank the materials according to their index of refraction, least to greatest. a .vtx, g ewcv4n*m+b0

Hold one hand close to your eye and focus on +ytigk.k ixb 7 tft+7p0m.* yaa distant light source through a narrow slit7p.*ttix+. ygyim kt7 fka 0b+ between two fingers. (Adjust your fingers to obtain the best pattern.) Describe the pattern that you see.

What happens to the dxebc dt5ph)jvvm uqg63 r81*:iffraction pattern of a single slit if the whole apparatus is immersed in (a) water, (b) a vacuum, ins x)dmgcphu1q:8rbvj3 t *56e vtead of in air.

For diffraction by a single slit, what is the efl b.a 4iq yh;yg,2lp7efect of increasing (a) the slit width, and (b) thh,y.iq apl2;y g47leb e wavelength?

What is the difference in the intep3ch3 h 41sqf3/e cjl/en)h jerference 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) closeln4 w ,bv gwp6*r5jx-l9g1yjl3mu*f dgy spaced sl4br 6w-gj*vfujx d5g 1 *wylpn93 gm,lits?

White light strikes (a) a diffraction grat/q(vm9gr + bztc ;x:gping, and (b) a prism. A rainbow appears on 9g(cb v:r; pmg+t/zxq a wall just below the direction of the horizontal incident beam in each case. What is the color of the top of the rainbow in each case? Explain.

For light consisting of wavelengths b 58o u bkq+b/l4i-7yn vhuoh8zetween 400 nm and 700 nm, incident normally on a diffraction grating, for what orders (if any) would there be overlap in the observed spectrum? Does 7uiy bho8-hv8kb n 4z+l/ o5uqyour answer depend on the slit spacing?

Why are interference:l+nacjz .l m)o.+w jb fringes noticeable only for a thin film like a soap bubble and not for a thick piece of glassj .:znlm+c.ljb owa)+, say?

When a compact disk (CD) is h*vpw5c/s w7 8gkbkr a,eld at an angle in white light, the reflected light is a8 c kv bpr75sww/g*,ka full 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 toges e92dr)*.d grjdvj/ cther farther from the center?

Some coated lenses appear greenish yello)naf rerr(6 k(w when seen by reflected light. What wavelengths do you r6(enaf k()rrsuppose the coating is designed to transmit completely?

A drop of oil on a pond appears bright at iyl :gz3s.s-ip 1wh1hkts edges, where its thickness is much less than the wavelengths of visible light. What can you say about the h-liyshzk:.1gp w31s index of refraction of the oil?

What does polarization tell us about the nature of light2 w j83)wl6/* ,qyim gjocdqay?

Explain the advantage of polarized sunglasses over normal 7es38o+x6 0)b hi2tzu;,h zryx qpav ntinted sunglasses.

How can you tell if a pair of sunglasses is polar(awg-xx l55v c)a/c ofizing or not?

Two polarized sheets rotated at an ang9 od3nx lgc75 e:afxt(le 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 thib0d1)y:4jf c2rxhvsz/:1 p76: a abpfoaiq l e Earth had no atmosphere?

If the Earth’s atmospher7em hc(+fhj +2sxpq;re were 50 times denser than it is, would sunlight still be white, or wou+mfh +s;7 jcqr(ehp2xld it be some other color?

  Monochromatic light falling on two slits 0.016 mm apart pr 5t(tol5nm q77dq0ttpk49q qbn6 fx8 boduces the fifth-order fringe at an 9d8f4qln 07b5(qkt 7bntp6q m 5tx qot8.8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 610 nm light is observed at an angle of 18oz-q,e6g/ jpw xy(zn *$^{\circ}\,$ when the light falls on two narrow slits. How far apart are the slits?    $\mu m$

  Monochromatic light falls on two venycah( (uu;o )r4x(dhfd0dp0 ry narrow slits 0.048 mm apart. Successive fringes on )0 dx(anhfud;rcoh(0 ud(y p4a screen 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 wavelength 65.-j)nkhta ep.p.ro h;9sud4w z9i*sj 6 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 s..o hien .d9 k*w9ajtss)hr upj;4zp-creen 3.6 m away?    cm

  Light of wavelength 680 nm falls on two slits and pt)5vt mrhfj;-gtrh 2/ roduces an interference pattern in which the fourth-order trh)tf vhg5-mj/; 2tr fringe is 38 mm 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 through two slits 0.58 mm apart, .nvv g1. n1hzrhow far apart are the second-order fringes for these two wavelengths orgvn 1 zvn..1hn a screen 1.0 m away?    mm

  In a double-slit experimen /*pj 9qhypoid4y qcp6x*j.gav;* z6st, it is found that blue light of wavelength 460 nm gives a second-order maximum at a certain location on t;gpq6q6sc phy pj4vzix9* a*/ *ojyd.he screen. What wavelength of visible light would have a minimum at the same location?    nm

Water waves having parallel crests 2.5 cm apart pa *cwyo7 wqbdmm6o3)c +ss through two openings 5.0 cm apart icmm6o o+y c)db3*w7wq n a board. At a point 2.0 m beyond the board, at what angle relative to the “straight-through” direction would there be little or no wave action?

Suppose a thin piece of glass is plq.mtrhvs w3xg;;wpr/sf yqw ::bhd 9 04y0r0xaced in front of the lower slit in Fig. 24–7 so that the two waves enter th xh;mgq p3w04y;b /rs::f0.9hxd wr yst rwv0qe 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, 3tsndr . ;8p7ixl6 xbnthe third-order maximum for light of wavelength 500 nm is located 12 mm from the central bright spot on a screen 1. trp.d3 67xnnl8isbx;6 m from the slits. Light of wavelength 650 nm is then projected through the same slits. How far from the central bright spot will the second-order maximum of this light be located?    mm

  Two narrow slits separated by 1.0 mm are illumina0y1ya sgvx1a 7ted by 544 nm light. Find the distance between adjacent bright fringes on g 7saayy10v1xa screen 5.0 m from the slits.    mm

  Light of wavelength 4ig9jd8 :e /c 5gykb ombef7f8wl9aqjt3y )g8+80 nm in air falls on two slits $6.00 \times10^{-2 }\;mm$ apart. The slits are immersed in water, as is a viewing screen 40.0 cm away. How far apart are the fringes on the screen?    mm

  A very thin sheet of plastic (n=1.60) covers one slit of a double-* j i1gzd n+9pmco1 quf0/fu;mslit apparatus illuminated by 640-nm light. The center point on the screen, instead of being a maximum, is dark. What ispf9mci fd /o*+q 1 mzu;nu0j1g the (minimum) thickness of the plastic?    nm

  By what percent, approximately, does the speed of j4m;.y4m ze.a;vxgoi red light (700 nm) exceed that of violet light (400 nm) in silicate flint glass? (See Fig. 24–e4m;jg vm.i.o4x z y;a14.)    %

  A light beam strikes a piece of glass at a 6nf 8(u o0/jqx4*e x k)*ngtqdq0.00$^{\circ}\,$ 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 conta06jxj jl j2u;(/ wr3l zxm8rjary2vn*ining 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 wi2thu: x6aol0gde, what is the full angular width of utla60 ho2x: gthe central diffraction peak?    $^{\circ}\,$

  Monochromatic light falls on a slit tha 7wemfnr(1(cg t 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 falll.)9-zqd ajjrq;6sd79 5s 7cxbwkn wis 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-nm light. What is tiv vd582-5;lnxnn 8bag 4bkk she width of the central l vdnsk8bkg5 a5;vnin42x8b-maximum (in cm) 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 +td c-(uu*7hq)vwo ax*yema 5 between the first bright fringes on either side of the centrawqt5d+m)x* a (c oau7u*v h-yel maximum is 32$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central diffraction peak on a screen 2.30 m bem i8 rq hin 5 x)ga+og++luz8wu4h:jw7hind a 0.0348-mm-wide slit illuminated by 589)rx+g wzom a7quh+li4 n+j5: u ghiw88-nm light?    cm

  When blue light of wav86u 0d)6 u2al pe8gmtxn7vptgelength 440 nm falls on a single slit, the first dark bands on either side of center are separ 7nxt)adul2t6 g0v 8p6gp8eum ated by 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 crel 22xd *si3ukfates a central diffraction peak that is 2f2 il3 xdu*ks9.20 cm wide on a screen that is 2.55 m away. How wide is the slit?    mm

  If a slit diffracts 650-nm light so that the di+fe6l3n7 w sveffraction maximum is 4.0 cm wide on a screen 1.50 m away, what will be the width of the diffraction maximume v+wn73fs e6l for light of wavelength 420 nm?    cm

For a given wavelengthkpne*o 39zzvbql)3j( bie48 a $\lambda$, 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 max4-nh9 fuz+9 arlhsj9v 25kyt aimum when falling on a grating whosnzhjh +f4kval 529rstu9- a y9e 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 third-order occ lk6d,xd8jd h*7t+lt xurs at an 18. ,ld7 ktt+h*d xd6jxl80$^{\circ}\,$ 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 fa8ccnrl te/xn(,f p :p0lling on a diffraction grating is observed at a 15.58,ctncre:lpp n0/ f (x$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction grating ah,0 enwy2 ene:0gyr -( fis.ghas $ 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 normallvk(msh -ve8w 59 qd:ld gt9o6o, ul0ejy on 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 xqprb9/+n i4d* j 0wk8cy5 pxpn1cgi;can be seen if a grating with 6000 lines per cm is illuminated with 633-nm laser lig n*/5pqi9nc x1j0giy rp+k;w c d8x4pbht? Assume normal incidence.   

  Two (and only two) full spectral orders can be sg ;;,wqd iij1(ry mf( lk2e,cyeen on either side of the central maximum when white light is sent through a diffraction gratin((ed rc;yyiil ;k mq jg,2f1,wg. What is the maximum number of lines per cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containing wavelengths from 410 nml txk om2i902r to 750 nm falls on a grating with l 09oxk2it 2rm$8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which produces monochromatic light of a knobc,g1dh, *pv5g 2mk mywn 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 measu3gaadp9plcq xva:*9 a9i; ,y i4 kd0rured 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 eop :5)crxham 8 5u*1u.niq zknm thick, what wavelength is most strongly reflected at the center of the outer surface when illuminated normally by wk85u 5)e a1. mio:q*hn rpuzxchite light? Assume that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the dark fringes in Example 24–8 if fmz4/cxonkw. r-; v7lthe glass plates are each 26.5lf ; 4vk7 .cxorm-w/zn cm long?    cm

  What is the smallest thickness of a soap fh.: lq4a9q* j7z/qm3 jy7zomv -dwnemilm $(n\;=\;1.42)$ 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 (a 39dze*k3jul) 3mao vil3u/g $\lambda\;=\;570\;mm$ 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 countif;ea *bc /j6lang the dark spot at the center) are observed when 550-nm light falls normally on a planoconvex lens re/lbf6aa j; c*esting 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 two32t.hgp. qz oc pieces of optically flat glass, as in Fig. 24–33. When light of wavelength 670 nm is incident normally, 28 dark lines are observed (with one .gpqh 2tocz.3 at each end). How thick is the foil?    $\mu m$

  How thick (minimum) should the air layer pn+(ot7v )gdehx s*o oghx0) 4be between two flat glass surfaces if the glass is to appear bright when 450-nm light is incident normally?0v hp)o7 )g xon+e4s*x(thgdo    nm
What if the glass is to appear dark?    nm

  vA piece of material, suspected of being a stolen dia07tjrkol v*)q.mezrn(g7 +o rmond $(n=2.42)$ 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 alcohoqaf7p0k ;2sao(o( sd ol $(n=1.36)$ 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 immersv uh3ac/f qr593yl qu .g)svr;ed in a liquid, the diameter of the eighth dark ring d95;suulrg cyav.qq)vh3f / r 3ecreases 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 interferp3nakt -w))s*1t,oot a qjc1lometer if 644 bright fringes are c,al3 t-t1s oj )*owqapcnt1)kounted when the movable mirror moves 0.225 mm?    nm

  A micrometer is conn2s t/gycvmw ;3i)cf0f ected to the movable mirror of an interferometer. When the micrometer is tightened down on a thin metal foil, the net n2;cg0wsf) yci3v/m tfumber 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 mirror kc y8ap6tx mu; q9b61c$M_1$ 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 throu7 0* 1wq p,nfkw(gn)evoe x.hugh a small glass container containing a cavity 1.30 cm deep. When a gas) 0kgfwe1e, *( qnn7xhupvw o. 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 orientexy. em qi o.h,)5ikpy; s8nv9ld 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 anc;)rsm8yw(fha,) iu r air–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a dia 27azlc y*/ t5w/jv1wdxlnlp5 mond submerged in water if the light is hitting the dj ta15vlp7 dcy/2 lwzl 5/*wxniamond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the light passing through themj pc4.lutf(7f is a maximum. At what angle should one of them be placed so that the inte( j4cu7.plftf nsity is subsequently reduced by half?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as to reduce the in lcij*o/j l 6j,0ot 89xcyk3kc 23jiqptensity of the incident unpolaro393k/0q,y i2 lkcijj6jjlc * tcx8opized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are oriented at lh 8o4e529( +uzu hdgaqdclg, 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 or1nrl m5v 8t,l(3 cxqekiented 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 h 83*9pfy *9cfzovpokoff the surface of water for light coming from beneath the surface? Compare to the angle fov3* o9hzo y 89p*ffkpcr 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 pass)emvl/xr-qbj7v -+f.i r2tk iy v6x 8tes through five successive Polaroid sheets, each of whose axis maf 6v-xjkm7titqb.r2x+riy8-)e vv l/kes a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength v3 yei1ocor-.f k7:nt$ 5.0\times10^{7 }\;m$ passes through two parallel slits and falls on a screen 4.0 m away. Adjacent bright bands of the interference pattern are 2.0 cm apart.
(a) Find the distance between the slits.    mm
(b) The same two slits are next illuminated by light of a different wavelength, and the fifth-order minimum for this light occurs at the same point on the screen as the fourth-order minimum for the previous light. What is the wavelength of the second source of light? $\lambda_2$    $ \times10^{-7 }\;m$

  Television and radio waves reflecting from mountains or airplanes can interfere 9pe3 np0n( t:p mpet6ie p5tz-with the direct signal from ep tpn9nzptp e(-ept :i 53m60the 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 grat l )7.t+dsv, j.rgvbheing with rd.e,7). lshjv+t b gv$ 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 59zzh 1qwl6-qh w*pfvsf/;-( wb0 nm passes through two narrow 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 maxw;1hl- q q6sv -*w(fhwzzpfb/imum than the 590-nm light. What is the wavelength of the unknown light? $\lambda_2$    nm

A radio station operating at 102.1 M-a baopl jd +5/9i:s0bik y3fdHz broadcasts from two 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, perpendicular to d at its midpoint and extending horizobddayik : 9b/l53of0 ji+asp-ntally 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 wide, vknnp- red-00 and blows a whistn-0 d0peknr- vle 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 doorway.    $^{\circ}\,$ either side of the normal.

If parallel light falls on a single slit of width D6rh, e:hyqv1wh2 + ya*:e ofab 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. When u(4z3ezkkqkl5i/(s9jzwh6 q normally incident 460-nm light is reflecthizwkqkzs q(5 (j9uel/k36z 4ed 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 tkdrqp+-i,c1l l .jh*jo be no second-orderijprj , *l-+d.clhq 1k spectrum for any visible wavelength?   $ lines/cm$

Show that the second- and third-order spectra of white lighbs d5 .z4w w uvgcy.961hn.fgkt produced by a diffraction grating always overlap. What wavelg5n k 1s.gz.fycbwvh 4.6 wd9uengths overlap exactly?

  When yellow sodium lig)izrl mhdi vod0x* ,0g*(lh 5eht, $\lambda\;=\;$ 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 gratinggt 1w.uuch(nfq xwh 8(h-cx2k. *jc:c with and the pattern is viewed on a screen 2.5 m from t -cfhcq*utukx x gj(21w c(hwnc..:8hhe 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 clearrmh 6gqaa c-;h.1 i/(8z eipaz material if a minimum of 150 nm thickness of it, when laid on glass, is needed to reduce reflection to nearly zero when light of 600 nm is incident p ;rii(.a/zmehq a6 -1h8ag cznormally upon it? Do you have a choice for an answer?

  Monochromatic light of variable wavelength is incident normnr49 u3g dugxan*s.3 ually on a thin sheet of plastic film in air. The refle 49x3u g3runang.u sd*cted light is a minimum only for $\lambda\;=\;512nm$ and $\lambda\;=\;640nm$ in the visible spectrum. What is the thickness of the film $(n=1.58)$? [Hint: Assume successive values of m.]    nm

  Compare the minimum thickness needed for an anti-p659dul uuxm 7reflective 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) thicb2c+i bw5)yfzn5nzjj39 o,zy kness for the air layer between two flat glass surfaces if the glass is to appear dark when 640-nm ,yz9b c5 n3wzjjfy2 oz5bni)+light is incident normally?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the light tr0x9v, 9cube ou4.fsc2xfodv 9ansmitted 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 conditco,vbxcs9 902 ef.fuu49xv od ions 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 offo h 9z3p2 pjk,tijcon.o9- dy5cni5 n4 a smooth lakek94jnp- c.zihon do5y, c5pi nj2o 9t3 is polarized most strongly?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as tj4) e 4869 vkhcgf nilm:x*ettt, nvx+o reduce the intensity of the incident unpolarized light by an additional factor (after the first Polaroid cuts it inlhem8it :vc,nnjg 4)6+4t xfkt*vx 9e half) of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light fallk2lw svc43( 1g ;z:ex*zwku uys on two polarizer sheets whose transmission axes are at right angles. A third polarizer is placed between the first two s*wx( zu2ygz;ve kw4c1 3k :sulo 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 tw/u fdwwjeb*:)r o1)s heir 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 l6)n:nyev.w d74nkkj at the Moon, which is approximately 38:ly ne .)vnkjk 6w4nd70,000 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 are each place( y4bes)- nuhad 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 a77c/w un-lfb mhfb zy )w09wq6 n0tz)$(n=1.34)$ 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 in phase with each /jfn efmn15z *;fjba3other. They are l;fn/f*5f nbem jj1za3 ocated 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 ankncoq0 dm-h 3shwkt9fl8*sdra7 ),f)ws) 3tzd 650 nm, enters a silicate flint glass equilateral prism ( ct oks*hf7 z) r 0d3ndwaf,k3q)wh)-slt8m 9sFig. 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 aplwxzp3r c nx91,h8 ta64v6jtnd 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