Does Huygens’ principle apply to sound waves? To water waves? pb(k-pj-hc0:2k dgiu 4hhd :tExplain.

What is the evidence ; x8pzp+k5-bvqdfo j4 that light is energy?

Why is light sometimes describ t5dd9p;dhq9vo x txts,:- somw.t;/qk8kh8a ed as rays and sometimes as waves?

We can hear sounds around corners, but we cannot see around corners; yet bo4sa ,z mbxyzzl;w4 s)7tn wnj2io ;i9;th sound and light ar t2z,iaszi4 ;w bmsxw;jnln9oz;y4 7) e waves. Explain the difference.

If Young’s double-slit experiment we*l 230y,u; mgi qg95sms32gdkdnwvj vre submerged in water, how would the fringe pattern bv d3l2j;k3 sn*iguym5g9g,ws qdm 02ve changed?

Monochromatic red light is incident on a doux *:y8dkdkx: bble slit, and the interference pattern is viewed on a screen some distance away. Explain how the fringe pattern would change if the red light source is replaced by a blue light sourc*yxkkd8:bd: x e.

Two rays of light from the same source destructively in+2c7 l kyvqzzu*mz-pb v0p-0u3dwk1h terfere if their path lengths -kh+0zlz7z1duq-mp 0 3pwvb2k ycvu* differ by how much?

Why was the observatcj.5o6u-uma (4i p tsjs(zze 3ion of the double-slit interference pattern more convincing evidence for the wave theory of light than the observationes5-s4m u(( 6aiz 3cp jtz.ujo of diffraction?

Compare a double-slit experiment for sound x q*wjk3iy3b8c s7e6dm* r8xiwaves to that for light waves. Discuss the similarities and differeb*3 rcx 7eq3s68yi wm*x8kdi jnces.

Why doesn’t the light from the two headlights of a distant car produce an inte 2(cdy7;/pggm i x1bjgrference pattern1 j7;xd(g/ g2cm ypgbi?

Suppose white light falls on the two slits of Fig. 24–7, but one slit i:tz jz3/trojgjjc2+v 32ilamxj / /t 8s covered by a red filtltzmc +r/tvojj/ijaj2 tj:2g33 x8/zer (700 nm) 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, ymygben2;qpq/*uz2 6 it is not broken down into colors as it is by a prism. Exp qy2u2bpz em6n/*qg; ylain.

For both converging and pmra9,fy ;)lbc, aw3kdiverging lenses, discuss how the focal length for red lig ,mplr bfw39a ,ck;a)yht differs from that for violet light.

A ray of light is refracted through three fhf9 j,r qwlfj64;gl 4different materials (Fig. 24–55). Rank the magf,jwl;hq 6l44fj9r f terials according to their index of refraction, least to greatest.

Hold one hand close to z5yz+;+ w*gow7au z t5u93k/yno swpb your eye 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 seewy/t zw +y*znoks puubo;9ga3w 7z55+.

What happens to the diffraction pattern of a single slit if the whole appar fu e83fn v4s0:szt8gnatus is immersedfvse8z0n: gfs8t u3n4 in (a) water, (b) a vacuum, instead of in air.

For diffraction by a single slit, whadw8fala,o e51xxaj38miyp ;) t is the effect of increasing (a) the slit wix8wax5)i 8 p3;1meaoyl,dfj a dth, and (b) the wavelength?

What is the difference in the inteouqy (+b8w2u2bqsm 8z rference 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 tm6w4qamrd 6* phe advantage of (a) many slits, (b) closely spaceddma*4wq6r 6pm slits?

White light strikes (a) a diffraction grating, an6s r 1qgn- e:/4vombzed (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 of the rainbomng:vez-e 64 os1rb/ qw in each case? Explain.

For light consisting of wavelengths between 400 nm and4 i6flbr ,-lgbg (.fxs 700 nm, incident normally on a diffraction grating, for what orders (if any) would there be overlap in the observed spectrum? Does your b xb(f4,-.l6r s ggilfanswer depend on the slit spacing?

Why are interference fringes noticeable only for a thin film like a soap bubb 8ix:vh h 4 bwa2:ufvm,77 l9tk- s6,jocxeevtle and not for a thick piece of g7mv:8 jlveto-ibfu v6hx9 274t kx eawc,s,h:lass, say?

When a compact disk (CD) is held at an angle in white light, the reflecuh(gdar78f(y ted light is a full spectrum (Fig. 24–56). Explain. What would you exp(h8 yur( fdga7ect to see if monochromatic light was used?

Why are Newton’s rings (Fig. zoe4qn13u4yruw-tfb 6 c v,9d24–31) closer together farther from the center?

Some coated lenses appear greenish yellow when seen by reflected light. What 4vj42 n2 x(rnu;xefkhwaveu 4xx ;j22e4nkhfvrn (lengths do you suppose the coating is designed to transmit completely?

A drop of oil on a pond appears bright at its edges, where its thickness is much nd7/i-h(ixk9j2omysu p:d+ d0e gmd3 less than the wavelengths of visible light. What can you sayym23h/e onj-x dm: 7s(+id0udgpd ik9 about the index of refraction of the oil?

What does polarization tell uw6y zk6/64jzxqpxvz n5npj4 , s about the nature of light?

Explain the advantage of polarizr 7j,bm, ka84wu*p xc.r x-gjzed sunglasses over normal tinted sunglasses.

How can you tell if a pair of sunglasses is poi3xyqyhf ii0:1 dlw .6uqq+- xlarizing or not?

Two polarized sheets hn2z ub-l8() e+ww7epcq* sowrotated at an angle of 90$^{\circ}\,$ with respect to each other will not let any light through. Three polarized sheets, each rotated at an angle of 45$^{\circ}\,$ with respect to each other, will let some light through. What will happen to unpolarized light if you align four polarized sheets, each rotated at an angle of 30$^{\circ}\,$ with respect to the one in front of it?

What would be the color of the sky if the Earth had no atmosphevnrnjl 1n43 yg4n0mwjl de8- o+,x5ssre?

If the Earth’s atmosphere were 50 times denser than it is, would sunlight;enu4hw593m u :g;8(plrt bbnp6y nfa still be white, or would it be some other colorwh ;u3lgar 86fneb pn ;b4u95pmt(yn:?

  Monochromatic light falling on two slits 0.016 mm apart produyoq x.b ygtvgd-wy,6294sy ;eat w6g2ces the fifth-order fringe at an-x,qg yvs t 49go; a2.yg2bdyyw66wte 8.8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 610 nm light is y9z ft2p04 oqai8nsy .observed at an angle of 18$^{\circ}\,$ when the light falls on two narrow slits. How far apart are the slits?    $\mu m$

  Monochromatic light falls on two very narrow slits 0.048 mm apart. ekpl/j3r .ezix6(lu9/ sn/jvSuccessive fringes on a screen 5.00 m away are 6.5 cm apart near the center of the pattern. Determine the wavelength and frequency of the light. ( jel9xjln/.uik rs/z6/3 vpe
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of light fr , 5v;jf2k+ fdrozmlt,om a He-Ne laser, with a wavelength 656 nm, falls on two very narrow slits 0.060 mm apart. How ,l 2dk 5f mvorz+jft;,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 hrng:-5l 8;fgp( rgc. cnkid 3pattern in which the fourth-order fringe is 38 mm from the centr;3:r(i.p c rdglgk nhn-cf 58gal 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 apar 20v5qmjjxudrf2r9.3dk1jxthp*4 c jt, how far apart are the second-order fringespm v 91x32c2*rhjjxfqukt0 45djdrj . 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 1xwxf32dn f un6q)pd)460 nm gives a second-order maximum at a certain location on the screen. What wavelength of visible light wo)f xnd 2wp1d63)fnq xuuld have a minimum at the same location?    nm

Water waves having parallel crests 2.5 cm apart pass6kck)vt*(f +ll2k.s*law ite through two openings 5.0 cm apart in a board. At a point 2.0 m beyond the board, at what angle relative to the “stratkw vf a+*(l c).kes li2tl*6kight-through” direction would there be little or no wave action?

Suppose a thin piece of glass isx5aj 9 uo(npa6 placed in front of the lower slit in Fig. 24–7 so that the two waves enter6ou9xn( j pa5a 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 fo +vywux/qnle-p:b,2 h h/t4b ir light of wavelength 500 nm is located 12 mm from the central bright spot on a screen 1.6 m from the slits. Light of wavelength 650 nm is then projected through the same slits. How far from the central bright spot will 2 4+hph:i/ bql/ye,ntwxv u-bthe second-order maximum of this light be located?    mm

  Two narrow slits separated by 1.0 mm are illqzpb5sh6l9 p2h 2qc7qdbpjv-w 8*s 9v uminated by 544 nm light. Find the dip blw p9zb 2q9d7-q*6scs85qjhvv ph2stance between adjacent bright fringes on a screen 5.0 m from the slits.    mm

  Light of wavelength 480 nm in air faenuw9jkvc6*(i+8p ngdo04mce ) 7yef lls 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=16 wroqpgp8oamd:h g75ka( :s +yri c11.60) covers one slit 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 ther (ri5gmhg+p 7 :ysc1a:oo1pda6k8 qw (minimum) thickness of the plastic?    nm

  By what percent, approximately, does the speed of redsb t8ba3r-.7t0nd,i4u yrxahc p y4q- light (700 nm) exceed that of violet light (400 nm) in silicate flint giarq4ap.7 hs n30-y-bcdty ,t8bux4rlass? (See Fig. 24–14.)    %

  A light beam strikes a piece of glass at a 60.0pf epcp6hg4v2 ;o*j v00$^{\circ}\,$ 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 tw 4+sf z-yw+pbfo 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 mmt l39 as2wp-6evz4itoe7)5m mzpeg;xn t p,)v wide, what is the full angular width of the central diffraction peak?7,zttop3xw mgv2mt) en 5)ae vpl 4z-9i6e;ps    $^{\circ}\,$

  Monochromatic light falls on a slit f6+sssmr 49lar5xen 1that 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 zh8ctsf +o/8 50t gwil520 nm 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-nm light. What is the wiq4ikg0 3iznz3v 6 rsc+dth of the central maximum (in cm) in the diffraction p zrs0n+6giz 3kv 4qi3cattern on a screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm falls on a slit.;( *uz5o)s 2gxwm tijurpa;5e If the angle between the first bright fringes on either side of the cum)urps(go j*i5 exta ; zw25;entral maximum is 32$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central diffraction peak on a screen 2.lkqe83it o*f,j 8/hhl30 m behind a 0.0348-mm-wide slit illuminated by 589-nm ligk /q,hh*ll8jf ti8o3eht?    cm

  When blue light of wavelength 440 nm fallsvl kr2ayj9 ld1v4h43u on a single slit, the first dark bands ondulvk 4 vh391aly 2jr4 either side of center are separated by 55.0$^{\circ}\,$. Determine the width of the slit.    $ \times10^{-7 }\;m$

  When violet light of wavelength 415 nm falls on a singleaatl5ffm 4 ,b5 slit, it creates a central diffraction peak that is 9.20 cm wide on a screen thafm,5 f4b aatl5t is 2.55 m away. How wide is the slit?    mm

  If a slit diffracts 650-nm light so that the diffraction maximujcny29/n4apldx 1 yiid2s0( bm is 4.0 cm wide on a screen 1.50 m away, what will be the widthlj yn12i dydpi 4nb0 s(a/cx29 of the diffraction maximum for light of wavelength 420 nm?    cm

For a given wavelengy0ha 9/2x loxb. yxz2ath $\lambda$, 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 f8jq3:wffvvt ,4nu4 w ld3e r1when falling on a grat8, :43 qvtnflrujw 4 wf1f3deving whose slits are $1.45 \times10^{-3 }\;cm$ apart?    $^{\circ}\,$

  A $3500-line/cm$ grating produces a third-order fringe at a 28.0$^{\circ}\,$ angle. What wavelength of light is being used?    nm

  How many lines per centimeter does a grating have if the third-ordr.268t; 9kwxx.6caquv5fu yh-md j eper occurs at an 1.6c9mx -d8je ;huv2xr p 5a6 qkwyu.ft8.0$^{\circ}\,$ 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 6dz:gdz9g*;ckwb; dkmi+ec3a x q n1q+mgf;1589-nm light falling on a diffraction grating is observed at a 15ka dz 161+f9gmqcxwk+cm en*qb; id; g:zg d3;.5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction gratino9zqyf:0 m( m i1yg)mag 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 o rhi fhu4(ywp3yp9*3xn 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 sy ci-3e67os n e2atc-zeen if a grating with 6000 lines per cm is illuminated with 633-nm laser light? Assume 2ac376-e csten - zyionormal incidence.   

  Two (and only two) full spectral orders can be seen on either side of the cen yv8 /l4)yftp m-b*a-wasy fh9tral maximum when white light is sent through a diffraction grating. What is the max8/4yt-v)ay-m*fwfas 9py hblimum number of lines per cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containing wavelengths from 410 nm to 750 nm falls on a gr3 b)uiaz8w-rj ating with 8)3warbjizu- $8500\;lines/cm$ 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 know 6jh it8qqhf 0f..jf c6nwu-u:n wavelength $\lambda\;=\;6.328\times10^{-7 }\;m$ is used to calibrate a reflection grating in a spectroscope. The first-order diffraction line is found at an angle of 21.5$^{\circ}\,$ to the incident beam. How many lines per meter are there on the grating?    $ \times10^{ 5}\;lines/m$

  Two first-order spectrum lines are measured bykglj4v/b.y a;i6x/ sc x bs;w( 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 wavelength is most strongtsvc6tn. 7dv 8d1a m7gly reflected at the center of the outer surface when illuminated normally by white light? Asdg8t.77vms6nt ca1vd sume that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the darwgu4asw-.j55i)sddki hl 8 / ak fringes in Example 24–8 if the glass plates are each 26.5 cm l5 isk4) lgwdu-w58 adahsj./iong?    cm

  What is the smallest thickneswq ) *2wzzjk2wsxdxh *b+9k4ns 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 yellg 1)bxz.byh4fow ($\lambda\;=\;570\;mm$ 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 Newtwk9fs* rs:k3kw2 f o+)mm+f jfon’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)sswwm +9o*ffkr:+kfj 2f3km glass surface (Fig. 24–31). How much thicker is the center than the edges?    $\mu m$

  A fine metal foil separates one end of twoauq . g7fft b-.k8smg6 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 at eac8mba k7 ggstu ffq.6.-h end). How thick is the foil?    $\mu m$

  How thick (minimum) should the agpo17q1fwr7 hx+a q 0xir layer be between two flat glass surfaces if the glass is to appear bright when 450-nm light is incidexha01wpqq1 7+grx f7 ont normally?    nm
What if the glass is to appear dark?    nm

  vA piece of material,xy xhoo8 s0-a7o95-do1a w xqj suspected of being a stolen diamond $(n=2.42)$ is submerged in oil of refractive index 1.43 and illuminated by unpolarized light. It is found that the reflected light is completely polarized at an angle of 59$^{\circ}\,$. Is it diamond? ----待选择----yesno 

  A thin film of alcohol o 0*ev/fo8c fw$(n=1.36)$ 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. 249 ksdw8+slvw rc m1t+2–31) is immersed in a liquid, the diameter of the eighth dw 8ksstw+ + 1cdvlmr29ark ring 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 bright fyu9:6q);;n suabpl(kb m: 9th : hcsxtringes are counted when the movable mirrorc6h (;q n kms tx:atbshy;:9 ubl):u9p moves 0.225 mm?    nm

  A micrometer is connected to the movable mirror of an interferometerpd nc.yvb*h c6rtg o/ 2i3)jo8. When the micrometer is tightened down on a thin metd rhovtcbgp 6j2in3 )y*oc 8/.al foil, the net number of bright fringes that move, compared to the empty micrometer, is 272. What is the thickness of the foil? The wavelength of light used is 589 nm.    $\mu m$

  How far must the mirro7xxax,p*-+gfst s80 xmar uj c8xxo0(r $M_1$ 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 small g5m)hr 6 lfwq hb.vsa. uwy 9x91/jo7l kfyyt4-lass 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 wavelength of 610 nm. Calculate the index of refraction of the gas, assuminj1lk-o. u ywvb4.5ya mrlwhq/9f 7 t6fy)xs9hg that the interferometer is in vacuum. $n_{gas}$

  

  Two polarizers are orientev6py3 u 22 nbr0dk+j4kag(om c a31vtvd 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–gla16d m/d g:s,aik:kymmss $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submerg8-z5 dfrkqkz5ed in water if the light is hitting kz8 -d55krzfqthe diamond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the li;1g f,otk8 fqky5xapllrq087 ght passing through them is a maximum. At what angll r 5;x7qt0fpogy1akl8fk8 q,e should one of them be placed so that the intensity is subsequently reduced by half?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as to reduc rp73 ,vz8pynfjq /ku1e the intensity of the incident unk1ru,/ z3pfyn7 vqpj8polarized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are oriented at 40 u s549t(bp3 5ub3fdma:nlva+ml5jlq$^{\circ}\,$ 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 ogtxpa+8-nmq.s (ie0n8l a 2ggriented 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 wat:b(y :mulp f,h9gc:a ver for light coming from beneath the surface? Compare to the angle for total internal reflection, and to Brewster’s angle from above the surfacf9gh,::v ly ca:upbm( e.
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 d1/ )-wgf. t3btvup,i0 pbudcthrough five successive Polaroid sheets, each of whose axis up,u1pw0if t)bdv tb d-gc 3./makes a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength zw 5 xlut;j:;x$ 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 airplanedfv5j(pis )3ls can interfere with the direct signal fif3ps(v5lj d)rom 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 di8o) o wt:krpmb+l m6x0ffraction grating with kx :opm bo+m 0lt68wr)$ 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 twy6f:x.at+x-b a e i0ddo narrow slits 0.60 mm apart. The screen is 1.70 m away. A second source of unknown:6itbx. e0ad+ dfax-y 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 light? $\lambda_2$    nm

A radio station operatj*v vv4n42qysing at 102.1 MHz broadcasts from two identical antennae at the same elevation but separated by an 8.0-m horizontal distance d, Fig. 24–jn*4 2yvsq4vv 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 doorwa)94ux/ mozkzcnyxclf f8. ) 4fy 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 clear84yxxc)uc nlf.z 4)z9m fk/f oly on the playground outside the doorway.    $^{\circ}\,$ either side of the normal.

If parallel light falls on a single slit of width D at al o:9swr-vb zlk tqi55pnn+,5 30$^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain beetle have a series of parallel,59qbcuiwzpk3k,f * nx 1t hque 1(wj56kpop5 lines across them. When normally incident 460-nm light is reflected from the wing, the wing appears bright when viewed at an angle of 51hp5,*wf poe5w6qu1 tkun 1kbz9 k p ,(3jx5cqi$^{\circ}\,$. How far apart are the lines?    nm

  How many lines per centimeter must a grating have if there is to be no sec6.f+s ko9cuxzeitf ghl*1sf h i2m( 91ond-order spectrum for any visibl 1ffsimo6hf +x1shkzlui.e 9 *t (9cg2e wavelength?   $ lines/cm$

Show that the second- and third-oo-ps30ov 2)zy7 mff)5 fqjigx+zjdl2 rder spectra of white light produced by a diffraction grating always overlap. What wavelengths overlap exactl ojszm20- fv))dffpy7 go5+2z 3lq xjiy?

  When yellow sodium lkzr x),ze orjn8)2uq4ight, $\lambda\;=\;$ 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 j6 (h4-t/ 3y qzjuokstw5w ib/d)jg:qthe pattern is viewed on a screen 2.5 m from thehti/ wgbu 4y5-sd/6) ot jj(q3 :wzqjk 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 materialt;5 pw 91m.touvg hw0f if a minimum of 150 nm thickness of it, when laid on glass, is w50p; o wf1ht tmg9.uvneeded 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 wavelength is incident normally on a thin sheet ie6/uc1a phw * :wmsw/of p:wpe/1/i* whwsumc 6alastic film in 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 needed for an anti-reflect-8;rhjn6 (sx8wpgf ulive 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 7tz .)bs aud1folmg1,ero) thickness for the air layer between two flat glass surfaces if the glass is to appear d1.)os,d m1ubl gatf7 zark when 640-nm light is incident normally?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the light transmitted throu 9nbzbh 5em),wgh a thin film layered on a flat piece of )9,n5 bbemhzwglass. 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 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 smooth ljy-5hjvosb9.vm ws.9 2nft 6uake v9v29w .fms6b u ho5sn.tj- jyis polarized most strongly?    $^{\circ}\,$

  At what angle should tu(chp;:x9wyrltj rl 1 y z4n-)he axes of two Polaroids be placed so as to reduce the intensity of the incident unpolarized light by an additional factor (after the first Polaroid cuts it in half) ofjnh(9y ru;ll xtz pyc:r-1w)4
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light fa8xhmwly6+ c4v ti txsv-)is /6lls on two polarizer sheets whose transmission axes are at right angles. A third polarizer is placed between the first two so that its axi6xh6cilv v8+yw xs/) it-4tm ss 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 u2.3xg7aas p lsuccession 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 throu4rj6:hs. dmhpgh a slit 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). Estir:mp46s d j.hhmate the width of the beam when it reaches the Moon.    km

  A series of polarizers are each placed agg. l. v1h 7p* *pjirmwfs9k +rkd(8rdt 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 s v8nuqsza309c r2ps6.v.qg c$(n=1.34)$ 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 phasek ec9vnvt zi*- :h4vm auyn807 with each other. They arezy8ave c*0n t9h-v:vmnu4 i k7 located at points $S_1$ and $S_2$, separated by a distance $d\;=\;175m$, Fig. 24–61. What are the first three points on the y axis where there will be destructive interference? (Destructive interference in this case means that a radio receiver placed at that point would pick up no signal).    m    m    m

  A parallel beam of light containing two wavelengths, 420 nm and 650 nm, e g+ detil*5c(qzx+1 honters a silicate flint glass equilateral prism (Fig+hzctgxe(* q5+loi 1 d. 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 and one wz2j n(y,pae8xy wh 32iith $R\;=\;18.4\,cm$ 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