Does Huygens’ principle apply to sound waves? To water waktxbvt6* rrg w,oia6xr 799h4 ves? Explain.

What is the evidence that ldk:g k3/lwkm +ight is energy?

Why is light sometimes described as rays and sometimesl/z8lhjty, y1 as waves?

We can hear sounds around corners, but we cannot see around corners; k j sxo0w25h)hwe1poc m0 a1-n+ wb3owyet both sound and light are waves. Explax1whw hkp +smbow02c j3o)0on-1a5 ewin the difference.

If Young’s double-slit experiment were+;l9acl *z v,vep s1bu submerged in water, how would the fringe pattern be changu *+,s;evzb 1lpa lvc9ed?

Monochromatic red light is incident on a douhy ufn,t nv i:o8+7me:ble slit, and the interference pattern is viewed on a screen some distance away. Explain how the fringe pattern would change if the red lighi :un: 8fh+ome7 nyt,vt source is replaced by a blue light source.

Two rays of light from the same source destructively interfere if tq xxv4m +5i:uv w(o8/n+fdb ejheir path lengths 4( q5odx jnf/:wi+ ub8+vxmevdiffer by how much?

Why was the observation of the double-slit interference pattern more convinciwgexvl2;7taw d:d34z tr1e8 it rme*+ ng evidence for the wtra7d2 8 zrx 1ilet* w+t4m3 dvg;e:ewave theory of light than the observation of diffraction?

Compare a double-slit experiment for sound waves8kl,m;. 5g0b gke. thfd5ytmj to that for light waves. Discuss the similarities and differkd8gj; , bf0t5ketgmm5y. h l.ences.

Why doesn’t the light from the two headlights of a distant car producerjgl)p56h h iuc( 1d3w an interference pattl6rdhu3hwij) cg5p1( ern?

Suppose white light falls on the two slits of Fig. 24–7, but one slit is coveru) d;u+ -atxk0,zcy w*pjejr1j 5m a8yed by a red filter (700 nm) and the other by a blue filter (450 nm). Describe the pattern on the screen. ,xz;k rdycaa )j*0ym 81 u+jtwj5pue-

When white light passes through a flat piec0mx,6 et r4x l;ra)igme of window glass, it is not broken down into colors as it is by a e r 0x6xtrga,4l)mi;mprism. Explain.

For both converging and diverging le a*(q.ekwgkm2.bp5 bwnses, discuss how the focal length for red light differs from that f* wq5 (mkbg2bwpe ak..or violet light.

A ray of light is refracted throusdz .gzsbl,l)9 ws0mmq1:s (tvm/ ps1yv ig9;gh three different materials (Fig. 24–55). Rank the materials according to their index of refracti zb1.m s9ws9gz;:di vm)sqt0p1g (llv y,sms/on, least to greatest.

Hold one hand close to your eye and focus on a distant light source through a olrs*2o . pdp(narrow slit between two fingers. (Adjust your fingers to obtain the best pattern.) 2rlo(.p* dsopDescribe the pattern that you see.

What happens to the diffraction pattern ):y9/r igcmjbf g gjyw1 -1x5cof a single slit if the whole apparatus is imm /wg9)c1rg jc5iybxy:-1mjfg ersed in (a) water, (b) a vacuum, instead of in air.

For diffraction by a single slit,f0.; 7liutmke what is the effect of increasing (a) the slit wu0 f7l; met.ikidth, and (b) the wavelength?

What is the difference in the interference patternukoy( 9f:cm/k 1or,bd s formed (a) by two slits $^{-4}\;cm^2$ apart, (b) by a diffraction grating containing $10^4lines/cm$?

For a diffraction grating, what is th25n zn l+r5 snk3ql*dse advantage of (a) many slits, (b) closely spaced slitsn*qs sl+5knnrz5dl 2 3?

White light strikes (a) a diffraction grating, and (b) a prism. A rainfgz)j em6 )* n,qu:hvsifr;2b bow appears o6q: )zju2v;mf h* if)besng ,rn 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 between 400 nm and 700 nm, )l )3pyw.vjoan;n d9d/y amo: incident normally on a diffraction grating, for what orders (if any) would there be overlap in n:y la.ywd/)vopj) 9a no;3mdthe observed spectrum? Does your answer depend on the slit spacing?

Why are interference fringes noticeable ojzp0bt 4u 1nw)nly for a thin film like a soap bubble and not for a thick 1tu4 )0zpjwbnpiece of glass, say?

When a compact disk ed :an- j2fo*a(CD) is held at an angle in white light, the reflected light is a full*e:oaadf2-n j spectrum (Fig. 24–56). Explain. What would you expect to see if monochromatic light was used?

Why are Newton’s rings (Fiuan; yx0c +s-8gq4u ghg. 24–31) closer together farther from the center?

Some coated lenses appear greenis l:qrrd,rq m3zo;/s 0rh:wa xsi;4+le h yellow when seen by reflected light. What wavelengths do you suppose the coating is d ;ll0d+ws/or 3mi rxqr4rq:;ase:z,hesigned to transmit completely?

A drop of oil on a pond appears brig2.dw qip*0v 7qi sd:xdk *c6liht at its edges, where its thickness is much less tha ldcv .:0wpi k67qd2i** isqxdn the wavelengths of visible light. What can you say about the index of refraction of the oil?

What does polarization tell us about*/rbzx 31w *(3h-/u1pqipq gd s rpjhz the nature of light?

Explain the advantage of polarized sunglasses ove1op)em *u*xji.f.md0.+klfa a aeh 2xr normal tinted sunglasses.

How can you tell if a pair of sunglasses is p9 +no dc+,kv bu:yq2omolarizing or not?

Two polarized sheets rotated at an anglenjd* 1tn-d l6s 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 ybilv-v( * pifab, efw(+hg/c,o nq8b/ec d;0atmosphere?

If the Earth’s atmosphere were 50 times denser than it is, would s(l-q*bs ( hjc qq7p:omunlight still beqosq(*p bh7m:qcj - l( white, or would it be some other color?

  Monochromatic light falling on two slits 0.a, (m/.maa v2svapm3 4:twwny016 mm apart produces the fifth-orderp a4ma,3w tym:s vm.n2v(aa/w fringe at an 8.8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 610 nm light is observed at an angle *rr rj 2kvl1+3 rf8fjhy(7xyiof 18$^{\circ}\,$ when the light falls on two narrow slits. How far apart are the slits?    $\mu m$

  Monochromatic light falls on two very nab09nvcfx m :sl3/-th d1c5bp b5os px3rrow slits 0.048 mm apart. Successive fringes on a screen 5.lpx h :bb3p v59fsb3sc5dtm1- n/ cx0o00 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 fif r* 9eyz-(wa wavelength 656 nm, falls on two very narrow slits (iz*wrf y-e9f 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 interferencxp *ksnq0ik-lx ,q ,9te pattern in which the fourth-order fringe is 38 mm from the censq-lik,qn *xk90x, p ttral 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, 2,e tf+5qpgx8qb gse1 how far apart are the second-order frsbfg g,5xqpee+q281 t inges for these two wavelengths on a screen 1.0 m away?    mm

  In a double-slit experiment, it is ;/24de3cpgu7hjele q found that blue light of wavelength 460 nm gives a second-order maximum at a certain location on the screen. What wavelength of visible light would have a mini;eeg4lqhdp7uj23/ec mum at the same location?    nm

Water waves having parallel crests 2.5 ci /rj9qab wk .s291sqwm apart pass 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 “straight-through” direction would there be little or no w/kjq ri1s. w9 bs2qa9wave action?

Suppose a thin piece of glass is placqem.i qn699 pli 5-yuced in front of the lower slit in Fig. 24–7 so that the two . iy9 p 96li5mncqu-qewaves 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 experimentq0wr) ,z2 tejp, the third-order maximum for light of wavelength 500 nm is located 12 mm from the central bright spot on a screen 1.6 m from the slits. Light of wavelength 650 nm is then projected through the same slits. How far from the central bright spot will the second-order maximum 2,rzw)tp0j e qof this light be located?    mm

  Two narrow slits separated by 1.0 mm are illumd.u(acxv3 o: pinated by 544 nm light. Find the distance between adjacent bright fro x (cvpua.3d:inges on a screen 5.0 m from the slits.    mm

  Light of wavelength 480.oa5 yg-unxgu8ot t c k-y:r,9 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-slit apparatus,ahd5 th1 pi;p illuminated by 640-nm light. The center point on the screen, instead of being a maximum, is dark. What is the (minimumpd h,pi a5t1;h) thickness of the plastic?    nm

  By what percent, approximately0gn0)9qncgo*bj 4 qly, does the speed of red light (700 nm) exceed that of violet lg40qc jygo*lbq n9n0 )ight (400 nm) in silicate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a bx87e htn(/ mtks2b,x8 8hgcmpiece 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 ligh(y: qbg17 n;res 8 px c0.k/prfhi,fhlt containing two wavelengths, $\lambda_1\;=\;450\;nm$ and $\lambda_2\;=\;650\;nm$, enters the silicate flint glass of an equilateral prism as shown in Fig. 24–58. At what angle does each beam leave the prism (give angle with normal to the face)?
$\theta_{d1}$    $^{\circ}\,$ from the normal
$\theta_{d2}$    $^{\circ}\,$ from the normal

  If 580-nm light falls on a slit r51 )a:sj,xz ;kcykdz 0.0440 mm wide, what is the full angular width of the central diffracka:;kzz, djxyrc15) stion peak?    $^{\circ}\,$

  Monochromatic light falls onqt dhj0/ k54;m3porg78wvg .7syqwg z a slit that is $ 2.60\times10^{ -3}\;mm$ wide. If the angle between the first dark fringes on either side of the central maximum is 35.0$^{\circ}\,$ (dark fringe to dark fringe), what is the wavelength of the light used?    nm

  Light of wavelength 520 nm falls on wja7nw i95iqjrqz3+2a 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 illumi0vspb u rwm8a u1-8f*knated by 450-nm light. What is the width of the central maximum (in cm) in the diffraction pattern on a screen 5.0 u- kmrs8avbupw1* 80fm away?    cm

  Monochromatic light of wavelength 653 nm falls on a slit. If the angle betwe nfa,8pbgbr-pl(6b :j en the first bright fringes on either side of the central maximum is prjg lfb(ba,:86b n-p32$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central 6b shu)4d1rtldkz6v2axov ph x1f b) --d3 si;diffraction peak on a screen 2.30 m behind a 0.0348-mm-wide slit illuminatebh1--)ov2 dx)hi66dx4l;s s p31vtu afz k rbdd by 589-nm light?    cm

  When blue light of wavelength 440 nm falls on a sin n+ (laeibh6 xuw pz):5d79ll yiut8.jgle slit, the first dark bands on either side5tn :( 7d8jil h+by p6alz) wui.uxle9 of center are separated by 55.0$^{\circ}\,$. Determine the width of the slit.    $ \times10^{-7 }\;m$

  When violet light of wavelength 4z(+5pi:s wv)n 5ldf( rbssl s515 nm falls on a single slit, it creates a central diffraction peak that is 9.20 cm wide on a screen that is 2.55 m5d f( +lrw pbsv)5lzsn(5:iss away. How wide is the slit?    mm

  If a slit diffracts 650-nm light so that the diffraction maximum is 4.0 vbidasa1 h48sxe)+ zr3t tm 07cm wide on a screen 1.50 m ah tzx)t7d0 814m rsv3baeais+way, what will be the width of the diffraction maximum for light of wavelength 420 nm?    cm

For a given wavelength ro vq.6y;h ni3$\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm 7-zb e3gqoyb-p 5ow8fq76v oalight produce a second-order maximum when falling on a gybwab zveq -fpoo78o5q6 3g-7rating 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.h4 b:nk5q6*,bjh-spqy t,bmwglaz ;* aff5 w third-order occurs at an 18gzf ;k s5 *6- hl:m.n,f*wbp,w5ayjh4bqatqb .0$^{\circ}\,$ angle for 630-nm light?    $ \times10^{3 }\,lines/cm$

  A grating has $8300\;lines/cm$. How many complete spectral orders can be seen (400 nm to 700 nm) when it is illuminated by white light?   

  The first-order line of 589-nm light falling on a diffractionlq5pig-3(0xj+ w7 x.j li nqbt grating is observed ajbl3(.+gp7jniqq x-0iw t 5 lxt 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 pgm; y)8pa 3idhas $ 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 on a jejdzoz+r. n ma2k/+ 6$9700-line/cm$ 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 ord3ru+d/bu(i uy g6k c;qer that can be seen if a grating with 6000 lines per cru (iq3/ +bg;kucdy6u m is illuminated with 633-nm laser light? Assume normal incidence.   

  Two (and only two) fullbil3;m(8t g7 l8ne aqt spectral orders can be seen on either side of the central maximum when white light is sent through a diffraction grating. What is tht blm;(gq nit3l e87a8e maximum number of lines per cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containing wavelengths from 410 nm to 750 nm falls on6 gwr xbxe(4)-q e 1)gtsvhzs06l9 hbe a grating with vx4h)6sqb g erlzbt1 hs(6 g0e)ew9- x$8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which produceqyz.a c-w:x i bespr9/m93 c:wof 4c,os monochromatic light of a known wavelength $\lambda\;=\;6.328\times10^{-7 }\;m$ is used to calibrate a reflection grating in a spectroscope. The first-order diffraction line is found at an angle of 21.5$^{\circ}\,$ to the incident beam. How many lines per meter are there on the grating?    $ \times10^{ 5}\;lines/m$

  Two first-order spectrum lines are m3x8st.k8 e :,kjco:7d jcfbf geasured 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 waveleng ht( b-l r,wqi3g.0hbyth is most strongly reflected at the center of the outer surface , -gl0bq( ri.b3thyhwwhen illuminated normally by white light? Assume that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the dark fringes in Example 24–8 if the glass platk0vp0fpn t2yi ,p- g3kes are each 26.5kt02nk-pppfv3 ,giy0 cm long?    cm

  What is the smallest thickness of ,.xr/tz pg,uw wkgd ,3ys9t9ea 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 greenish8qaya8ep1gw pb/de g 4m;p 42p 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 and 31 dark Nenpo4tx dln9am p4840cwton’s rings (not counting the dark spot at the center) are observed when 550-nm light falls normally on a planoconvex lens resting on a flat glass surface (Fig. 2 40c otpnxmda 49pnl484–31). How much thicker is the center than the edges?    $\mu m$

  A fine metal foil separates one end of two pieces of optically flat glass, as in3p.xq9g99mj xg0 sqd( k3adah Fig. 24–33. When light of wavelength 670 nm is incident normally, 28 a gd x9qs.m3 qkg0ha9 j(3dpx9dark lines are observed (with one at each end). How thick is the foil?    $\mu m$

  How thick (minimum) should the a1- (. uk/p9i+cygic zaf k+je+h h:kazir layer be between two flat glass surfaces if the glass is to appear bright when 450-nm light is incident normafkiey-+ig khpcukh z c1z/ +a.9:+(a jlly?    nm
What if the glass is to appear dark?    nm

  vA piece of material, suspected of being a stolen diw 2rgab7;5i5 2 0ds rf+uqxnjj3eo2 szamond $(n=2.42)$ 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 s* dbr -h ay ;0joq:y36ofy.qf$(n=1.36)$ 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 apvew j2.6w2 oipparatus (Fig. 24–31) is immersed in a liquid, the diameter of the io2wp 2jev6w. eighth dark 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 interfr-zb a+r1, qe2/k/ or azmohu)erometer if 644 bright fringes are counte,1u /orq/b+zhakrom )-ea2rz d when the movable mirror moves 0.225 mm?    nm

  A micrometer is conneh eac o z1+3ns 7ev: me,,zpdk,0 8mdz:d5kqzccted to the movable mirror of an interferometer. When the micrometer is tightened down on a thin metal foil, the net number of bright fringes that move, comparv0oz,,k38z+edd5n:qk mhzem eaz , s1cc:dp 7ed 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 /whlv p12u+6 5)u a)gjdakjwt$M_1$ 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 aow(5dwvnt 7vg)z 8:1 x1cxwssmall 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 wavelength of 610 nm. Calculate the index of refraction of the gasn1twa z7:)c1 (ow5 dgv xwsxv8, assuming that the interferometer is in vacuum. $n_{gas}$

  

  Two polarizers are oriented at 650hs3be v l*k9jb0by pq2h )6zqn/+wmh$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s angle for an air–glao */;pt irz2f lqodp,1ss $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle +iltkb)y8kf; 2 lh2 x eh5vqn;for a diamond submerged in water if the light is hitting the diamondbkl vyilh2;582fn qxth)+k ;e $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligomuh91n4t vi c8 jq9l1ned so that the light passing through them is a maximum. At what angle should one ov98ti 14qjnh9 mo1uclf them be placed so that the intensity is subsequently reduced by half?    $^{\circ}\,$

  At what angle should the axes of two -sh 1wv*raei6Polaroids be placed so as to reduce the intensity of the incident unpolarized light to -16wa*eisv hr
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are oriented at 40e wk7)k( -p+prksnfkh9 0c3p vjxi9j *$^{\circ}\,$ 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 orienk g1th;l2q- qnted 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 nytf 2/u.grlwq(5 e/tfor reflections off the surface of water for light coming from beneath the surface? Compare to the angle for total internal reflection, and to Brews/./teyqu2tl g rn fw(5ter’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, 8vq or vu axdn-xzr:w69g+76e each of whose axis 76 +q : 6ga vz8rwnrxvdx-eou9makes a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength 0v:m;k )r:yqcbp(ph 6*2ych l5bsxnp$ 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 inte r,z . -ro/foioax.(mzrfere with the direct signal from the statioz,ri-(o .moo/xf a rz.n.
(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 di 3dpbf8wkr,i6us mlf m-f0cmqv96 -a/ffraction grating with v-f pic6l/ fa 6qdmb90ws,fu-8mk 3mr$ 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 thre2m fta05htektq 5k 96; z-lkpough 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 maximum than the 590-nm light. W2et9kt5;56tzk - phlm eaqfk0 hat is the wavelength of the unknown light? $\lambda_2$    nm

A radio station operating at 102.1 MHz broadcasts from t e+godkjpu6 6)wo identical antennae at the same elevation but separated by an 8.0-m horizontal distance d, Fig. 24–60. Aj 6po)uegd+6k maximum signal is found along the midline, perpendicular to d at its midpoint and extending horizontally in both directions. If the midline is taken as 0$^{\circ}\,$, at what other angle(s) $\theta$ is a maximum signal detected? A minimum signal? Assume all measurements are made much farther than 8.0 m from the antenna towers.

  A teacher stands well back from an outside doorway 0.88 m widk, 26c5k6: izpr1;purj ) x +pr(1xsmn zwpayae, and blows a whistle of frequency 750 Hz. Ignoring reflections, estimate at what angle(s) it is not possible to hear the whistle clearly on the playground outside the doorw(z)m r6k2 6p5p1znki;a,xsw r c1x :pypuj+ra ay.    $^{\circ}\,$ either side of the normal.

If parallel light falls on a single slit ofxl6oo akh.86gjus5/c v0e s0 f width D at a 30$^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain beetle have a seriqxjhzi do0h84b -; k 5aihc*4ees of parallel lines across them. When normally incident 460-nm light is reflected from the wing, the wing appears bright whaed5-;4ikh8b jh4z ixo*qc0hen viewed at an angle of 51$^{\circ}\,$. How far apart are the lines?    nm

  How many lines per centimeter must a gratingh4icl typ 8nm,-cix63 have if there is to be no second-order spectrum for anyc 3 mip, cl-486ythnix visible wavelength?   $ lines/cm$

Show that the second- and third-order spectra of white light pror2 k/rkr:avkejf;g:6 ;gcnl 3duced by a diffraction grating always overlap. What wavera;;:k3c k :r/enfjv6 g 2lkrglengths overlap exactly?

  When yellow sodium light,b-jlr de*9 bvm p81q/n $\lambda\;=\;$ 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 diffractio *p7;kc pplnw(n grating with and the pattern is viewed on a screen 2.5 m from the grating. The incident light beam consists of two wavelengt( pp7 nk;*clpwhs, $\lambda_1\;=\; 4.6\times10^{ -7}\;m$ 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 refr2bl 4uiw*sto*+j e 9tllt4e q:action of a clear material if a minimum of 150 nm thickness of it, whet:qe usl9*bli* 4wt jet4l2+on laid on glass, is needed to reduce reflection to nearly zero when light of 600 nm is incident normally upon it? Do you have a choice for an answer?

  Monochromatic light of gnf7vba)dm4* variable wavelength is incident normally on a thin sheet of plastic film in air. The reflected light is a minim7vdagbf*4 )n mum 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 7:3q2x0o,kgoi2s332asq fs jn-t;nhcuii hd 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 layer betwe u+8(v 9oyvm1u)e ly:jwh4prten two flat glass surfaces if the glass is to appear d 4ur:m +upv8oew9j(vt1 )lhyyark when 640-nm light is incident normally?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the light transmitted through a thin filq8d6nio9aya , m layered on a flat piece of glass. Draw a diagram, similar to Fig. 24–30 or 24–36day9q8o 6n ia,, 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 kcox4fb86f.u 57fagc lakeu k5 f86x7fcfoagb.c4 is polarized most strongly?    $^{\circ}\,$

  At what angle should the axes of two Polaroi+hsn1kz .igc .. sdr)hds be placed so as to reduce the intensity of the incident unpolarized light by an additional factor (after hssghidz.+). cknr. 1the first Polaroid cuts it in half) of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light falu-lyxu:dec.y qy1( ; cls on two polarizer sheets whose transmission axes are at right angles. A third polarizer is placed between the first two so that its axis maeyccu1qyl;:yx - u.d( kes 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 successi)jk7.x(vv h p4suhh;bj b x 1k-1tz)svon with their axes vertical, at 30$^{\circ}\,$ to the vertical, at 60$^{\circ}\,$ to the vertical, and at 90° to the vertical.
(a) Calculate what fraction of the incident unpolarized light is transmitted by the four polarizers.
(b) Can the transmitted light be decreased by removing one of the polarizers? If so, which one?
(c) Can the transmitted light intensity be extinguished by removing polarizers? If so, which one(s)?

  A laser beam passes through a slit of widtraib j(*81g (d zjafh8h 1.0 cm and is pointed at the Moon, which is approximately 380,000 km from the Earth. Assume the laser emits waves ofd8aa(( ig jjfzbr8h 1* 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 placedodik-i9p y/eppb:/( t 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 , i-lfwmvh4uxb6a . *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 phase wi 9 r6ss6r( inzeben:8xh9 ht.n/k4s vxth each other. Thhb (nzx. her ne:r/s9n8 9tk6s6vxi4s ey are 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 wavelu7 )*um5ghfusd39z1lg4 t jaz engths, 420 nm and 650 nm, enters a silicate fj usz)1tdguf9hgam 3uz4* 57llint glass equilateral 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 and one with n4+lboshr -3i56oz2(w rqjzv $R\;=\;18.4\,cm$ 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