Why is the depth of field greater, and the image sharper, when a01:udeuv 8b iu camera lens is “stoppeudi: 0u1vbu8ed down” to a larger f-number? Ignore diffraction.

Describe how diffraction affects the s6rhj f/t-.jnp/4s)jz+3 pzgix ys/qz tatement that the depth of field is greater and the imanzy.szsjjq3/i h)prtx+//4fp-jzg 6 ge sharper when a camera lens is “stopped down” to a larger f-number.

Why must a camera lens be m y8.(7v8 lulgoc2cvpk oved farther from the film to focus on a closer object 8l.8 ( c7vol2kpgvyuc?

Why are bifocals needed mainly by older persons and not genl7 )g6-qu 5 7xwwg2. 1jsiubxpd.bgyg erally by younger peoui1 b 5xyg 6 -gqpl2)uxbdggwj.w 7s7.ple?

  Will a nearsighted person who wears corrective lenses in her glasses be accyao0e w/tst7h9 r 79gn9 *vbble to see clearly und 0scv9 7g9a*con ehbtt7/rw9y erwater when wearing those glasses?  ----待选择----yesno Use a diagram to show why or why not.

You can tell whether a pene pbr( xrr8fuq2c378 rson is nearsighted or farsighted by looking at the width of the face through their glasses. If the person’s face appears narrower through the glasses (Fig. Below), is the perrb(u frcp88eq2 x3r7 nson farsighted or nearsighted?

In attempting to discern distant details, people will/r:ad4i gnp9 q sometimes squint. Why does this d n4:g/ap9irq help?

Is the image formed on the retina of the human eye upright or inv/3xg famxrhi)l1 id- 2* sp0ca9 mxe;qerted? Discuss the implications of thmm*f;2q xixe /lsaghp a0 i1-rd3x9)cis for our perception of objects.

The human eye is much like a camera — yet, when a camera shutter m6x9xu; z)h uuhfto )8yqa(o/is left open and thehaz;ho) 8fuumxo)qy (/x u t96 camera is moved, the image will be blurred; but when you move your head with your eyes open, you still see clearly. Explain.

  Reading glasses use converging lenses. A sc x *,bj(sk5ssimple magnifier is also a converging lens. Are reading glas*sb xjs,5 kc(sses therefore magnifiers? ----待选择----yesno  Discuss the similarities and differences between converging lenses as used for these two different purposes.

Inexpensive microscopes fos/ 8 qcmqatthwov88u) f-3hj0r children’s use usually produce images that are colorua8t 8q)w-qs/h ojf30vhm tc8ed at the edges. Why?

Spherical aberration in a s2 xzf97 l3jcmthin lens is minimized if rays are bent equally by the two surfaces. If a planoconvez72f9ms3 xcjlx lens is used to form a real image of an object at infinity, which surface should face the object? Use ray diagrams to show why.

Which aberrations present in a simple lens are not present (oru1(bbyqvp k x2dw +7u(m-dw3d are greatly reducedmwd+v7 b(xu(py 2 dq31w-d kbu) in the human eye?

Explain why chromatic aberration occurs for thin lenses 5w5yma , ws+1(sy 53wgdf drqhbut not for mirrors.

  By what factor can you improve resolution, other things being equal, 4nbtht) .k3n+d llhs +3k;wsi if you use tsnllhnsi 4kdhb+ wt.33k +) ;blue light ($\lambda=450mm$) rather than red (700 $nm$)?  

Give at least two advantages for the use of large reflecting mirrors in, j*mp1xlr w:9ji* zfa astronomical telesr lz9*w:ai1fjj x,p*mcopes.

Which color of visibl yt;os9czu y,rp17zj 2e light would give the best resolution in a microscope? Expla; uytpos29,1zjyczr7 in.

  Atoms have diameters of afqt w 4()gs ,lwjf,*fubout $10^{-8}\,$cm$. Can visible light be used to “see” an atom? ----待选择----yesno  Explain.

  A 55-mm-focal-length(u6(y.ok9 r6vbk gh wp lens has f-stops ranging from $f/1.4$ to $f/22$. What is the corresponding range of lens diaphragm diameters?    $\mathrm{mm}\leq D\leq$    $\mathrm{mm}$

  A television camera lend;bd, oh*8 4ec v7fnugs has a 14-$cm$ focal length and a lens diameter of 6.0 $cm$. What is its $f$-number? $f$/  

  A light meter reports that a camx+2bcx4 r a;qxera setting of $\frac{1}{250}\,s$ at $f/5.6$ will give a correct exposure. But the photographer wishes to use $f/11$ to increase the depth of field. What should the shutter speed be?$t_2$ = 1/   s

  A properly exposed photograph is ec )9(2nk)mphi-8 iuvjdbyw7 taken at $f/16$ and $\frac{1}{60}\,s$ What lens opening would be required if the shutter speed were $\frac{1}{1000}\,s$? $f$/  

  If an $f$ = 135-mm telephoto lens is designed to cover object distances from 1.2 m to $\infty $, over what distance must the lens move relative to the plane of the film?    mm

  A 200-mm-focal-length lens can be adjuste,xals gdwka ac85): w6 w42at xqmk*.db :3vhad so that it is 200.0 mm to 206.0 mm from the film. For what range of object distances can it be adjusted? t.wcw:4avq5:ga 6 *x2dh sal)3dxawbk8k,m a   $\mathrm{m}\leq d_{\circ}\leq\infty$

  A nature photographer wishes to photograph a 28-mtall tree from j.9f5db nt5h3ii0 dj jd45nqe a distance of 58 m. What focal-length lens should945n0edf jtnd iq . d5hi5bj3j be used if the image is to fill the 24-mm height of the film?    mm

A “pinhole” camera uses a tiny pinhol4uodnjjav5 .eto h997 -um(nle instead of a lens. Show, using ray diagrams, how reasonably sharp images can be formed using such a pinhole camera. In particular, on un-.ev jl49djth om(57 9uaconsider two point objects 2.0 $cm$ apart that are 1.0 m from a 1.0-mm-diameter pinhole. Show that on a piece of film 7.0 $cm$ behind the pinhole the two objects produce two separate circles that do not overlap.

  Suppose that a correct exposure i jq49w ,m7o/+ ap.k+tz6cg glduua :hns $\frac{1}{250}\,s$ at $f/11$ Under the same conditions, what exposure time would be needed for a pinhole camera (Problem 8) if the pinhole diameter is 1.0 mm and the film is 7.0 $cm$ from the hole? $t_2$ = 1/   s

  A human eyeball is about 2.0 bc4( hde1 drg017p9 +viuvtws$cm$ long, and the pupil has a maximum diameter of about 8.0 mm. What is the “speed” of this lens? $ f-stop$ = f/  

  If the nearsighted person in Example 25–6 wore contact lenses corrected yt 9;)yu5cu0vbw .g0spagb s1for the far poinuu5b.0;9g s wvt1y) ygp0csabt $(=\,\infty)$ show that the near point would be 41 $cm$. (Would glasses be better in this case?) glasses would be  ----待选择----betterworse 

  Reading glasses of what power are nee4x*irmwz9/ t f)4nrh4x sbep/ded for a person whose near point is 115 $cm$, so that he can read a computer screen at 55 $cm$? Assume a lens–eye distance of 1.8 $cm$.+    D

  A person has a far point os0 ) l si.b/snw*g8wghf 14 $cm$. What power glasses would correct this vision if the glasses were placed 2.0 $cm$ from the eye?    What power contact lenses, placed on the eye, would the person need?   

  A person struggles to read by holding a book at arm’s lengje3cq q258b (dp;ntekth, a distance of 45 $cm$ away (= near point). What power of reading glasses should be prescribed for him, assuming they will be placed 2.0 $cm$ from the eye and he wants to read at the normal near point of 25 $cm$? +    D

  A person’s left eye is corr +dw7:i1obojnw4 y (xaected by a $-3.50-diopter$ lens, 2.0 $cm$ from the eye.
(a) Is this person’s left eye near- or farsighted?  ----待选择----nearsightedfarsighted 
(b) What is this eye’s far point without glasses?    cm

  A person’s right eye can see ofya9 +qo)wo 5,x/ziow8mjn /w bjects clearly only if they are between 25 $cm$ and 75 $cm$ away.
(a) What power of contact lens is required so that objects far away are sharp? -    D
(b) What will be the near point with the lens in place?    cm

  About how much longer is the nearsightn gcnbhcki.4u a)wsk x-1s2,*ed eye in Example 25–6 than the 2.0 $cm$ of a normal eye?    cm

  One lens of a nearsighted person’s eyegljmzx lxf 3w;v06;u1kdasses has a focal length of $-22.0 \, cm$ and the lens is 1.8 $cm$ from the eye. If the person switches to contact lenses that are placed directly on the eye, what should be the focal length of the corresponding contact lens?    cm

  What is the focal length of the eye–lens system when viewing an ongu78j u+9jd4jk 5ra gbject
(a) at infinity,    cm
(b) 33 $cm$ from the eye? Assume that the lens–retina distance is 2.0 $cm$.   cm

  A nearsighted person has nea t7,hdcjsfvh+lg:scq 11)zs /r and far points of 10.0 and 20.0 $cm$, respectively. If she puts on contact lenses with power $P\,=\,-4.00D$, what are her new near and far points?
near point    cm
far point    cm

  What is the magnification of a lens used with a relaxey7sg1o)ya:p zgfg2hv s(mh:- d eye if its focal length z)yvgsagh hfmp2s:y-1:o 7(gis 12 $cm$? =    $\times$

  What is the focal length of a magnifying g(-n;qy osa-o4(kpuqdh2k d8 x4e 9o zolass of $3.5\times$ magnification for a relaxed normal eye?    cm

  A magnifier is rated athbc1:fr p*. 9x94xhid8cqdpn $2.5\times$for a normal eye focusing on an image at the near point.
(a) What is its focal length?    cm
(b) What is its focal length if the $2.5\times$ refers to a relaxed eye?    cm

  Sherlock Holmes is using a 90+wk)jmxqodlp uut k5 5l 8:2*tqvt,i.00-$cm$-focal-length lens as his magnifying glass. To obtain maximum magnification, where must the object be placed (assume a normal eye), and what will be the magnification?
$d_o$ =    cm from the lens
M =    $\times$

  A 3.30-mm-wide beetle is viewed with a 9.wde9my 20b68gu fgb n,50-$cm$-focal-length lens. A normal eye views the image at its near point. Calculate
(a) the angular magnification, =    $\times$
(b) the width of the image,    mm
(c) the object distance from the lens.    cm from the lens

  A small insect is placqdy4z+f ;cid8 ed 5.55 $cm$ from a $+6.00-$cm$-focal-length$ lens. Calculate
(a) the position of the image,    cm
(b) the angular magnification. =    $\times$

  A magnifying glass with a focal length of 8.5 j l/dic tgj4i9bh92)zx3qlh0$cm$ is used to read print placed at a distance of 7.5 $cm$. Calculate
(a) the position of the image;    cm
(b) the angular magnification. =    $\times$

  A magnifying glass is 2(6yzba:izpl o am,8t rated at $3.0\times$ for a normal eye that is relaxed. What would be the magnification of this lens for a relaxed eye whose near point is
(a) 55 $cm$, =    $\times$
(b) 16 $cm$? Explain the differences. =    $\times$

  What is the magnification of an astronomical telescope whose objectivp( qsgrhbz6z j+8 1zpzt 62gr,e lens has a focqz ,gz6trs b g28jprz+z6p( 1hal length of 76 $cm$ and whose eyepiece has a focal length of 2.8 $cm$? What is the overall length of the telescope when adjusted for a relaxed eye?
M =    $\times$
L =    $\times$

  The overall magnification of an astronomical telescopeome(u ln1- r87+qxe ze is desired to be 25$\times$. If an objective of 78$-cm$ focal length is used,
what must be the focal length of the eyepiece? $f_e$ =    cm
What is the overall length of the telescope when adjusted for use by the relaxed eye? L =    cm

  An 8.0$\times$ binocular has 2.8$-$cm$-focal-length$ eyepieces. What is the focal length of the objective lenses?    cm

  An astronomical telescope has an obm6i;4 udmnb l 1mjs b/o,/x-hsjective with focal length 85 $cm$ and a $+35-D$ eyepiece. What is the total magnification? =    $\times$

  An astronomical telescope has its two lenses sp3vy/jvlf c.fgamf 8fw-r0*x k r*y3-paced 75.2 $cm$ apart. If the objective lens has a focal length of 74.5 $cm$, what is the magnification of this telescope? Assume a relaxed eye. =    $\times$

  A Galilean telescope adjusted for a rel/*efd1+wuu l+ xf3v r,0q59e zydtkpjaxed eye is 32.8 $cm$ long. If the objective lens has a focal length of 36.0 $cm$, what is the magnification? =    $\times$

  What is the magnifying power of an astronomical telescope using a renv (7oq.m;1ezeylo ( xflecting mirror whose radius of curvaturv1mn.x((ol ze;7 qeoy e is 6.0 $m$ and an eyepiece whose focal length is 3.2 $cm$? =    $\times$

  The Moon’s image appears to be magx9 ,2z. lz-r4rchas 2ov2pvwonified 120$\times$ by a reflecting astronomical telescope with an eyepiece having a focal length of 3.2 $cm$. What are the focal length and radius of curvature of the main (objective) mirror? M =    m r =    m

  A 170$\times$ astronomical telescope is adjusted for a relaxed eye when the two lenses are 1.25 m apart. What is the focal length of each lens?
$f_e$ =    mm
$f_o$ =    m

  A reflecting telescope (Fig. Below) has a radius of curv )o 7 +fv4jqe/hme)mqkvf9v 1gature of 3.0 m for its objective mirror and a radius of curvatur ev)e94 /m k )+foh1qfqjmgv7ve of $-1.50m$ for its eyepiece mirror. If the distance between the two mirrors is 0.90 m, how far in front of the eyepiece should you place the photographic film to record the image of a star? $d_{2i}$ =    m

  A microscope uses an ja/g u ho yeh./.47lbdeyepiece with a focal length of 1.40 $cm$. Using a normal eye with a final image at infinity, the tube length is 17.5 $cm$ and the focal length of the objective lens is 0.65 $cm$. What is the magnification of the microscope? =    $\times$

  A 620 $\times$ microscope uses a 0.40-$cm$-focal-length objective lens. If the tube length is 17.5 $cm$, what is the focal length of the eyepiece? Assume a normal eye and that the final image is at infinity. $f_e$ =    cm

  A 17-$cm$-long microscope has an eyepiece with a focal length of 2.5 $cm$ and an objective with a focal length of 0.28 $cm$. What is the approximate magnification?    $times$

  A microscope has a 12.5 26 xkpalphueo4+5yl 0$times$ eyepiece and a 59.0$times$ objective lens 20.0 $cm$ apart. Calculate
(a) the total magnification,    $times$
(b) the focal length of each lens, $f_e$ =    cm $f_o$ =    cm
(c) where the object must be for a normal relaxed eye to see it in focus. $d_o$ =    cm

  A microscope has a 1.*eqvd-a p8jg2 8-$cm$-focal-length eyepiece and a 0.80-$cm$ objective lens. Assuming a relaxed normal eye, calculate
(a) the position of the object if the distance between the lenses is 16.0 $cm$, $d_{oo}$ =    cm
(b) the total magnification.    $times$

  Repeat Problem 61 assur.poxh) y.njo q9:v*bx3d3( b r-paacming that the final image is located 25 $cm$ from the eyepiece (near point of a normal eye). $d_{oo}$ =    cm   $times$

  The eyepiece of a compound microscope has a focal length n4, b20usk qnlof 2.70 $cm$, and the objective lens has $f=0.740\mathrm{~cm}$. If an object is placed 0.790 $cm$ from the objective lens, calculate
(a) the distance between the lenses when the microscope is adjusted for a relaxed eye, $l$ =    cm
(b) the total magnification.    $\times$

  An achromatic lens is made of two very thin lenses, pc x ynq.-)1i4 :h5nwk6nn lnhjlaced in contact, that have focal len.knn6x5c- h4i)jl yn: nqw1nhgths of $f_1=-28\mathrm{~cm}$ and $f_2=+23\mathrm{~$cm$}.$
(a) Is the combination converging or diverging?  ----待选择----convergingdiverging 
(b) What is the net focal length?    m

  Let’s examine spherical aberration in a particular situatio-zh n kq1et/dh/q- v35( tfhojn. A planoconvex lens of index of refraction 1.50 and radius of curvature qo-5/1 j3vz/(n -hhh eqd fttk$R=12.0\mathrm{~$cm$}$ is shown in (Fig. Below). Consider an incoming ray parallel to the principal axis and a height h above it as shown. Determine the distance d, from the flat face of the lens, to where this ray crosses the principal axis if
(a) $h=1.0\mathrm{~$cm$},$ $d_1$ =    cm
(b) $h=6.0\mathrm{~$cm$},$ $d_2$ =    cm
(c) How far apart are these “focal points”? $\Delta d$ =    cm
(d) What is the radius of the “circle of least confusion” produced by the $h=6.0-\mathrm{~$cm$},$ ray at the “focal point” for $h=1.0\mathrm{~$cm$},$? r =    cm

  What is the angular resolution limit (degrees) set by diffracti a2v 1el-w4re;dy(d6qc+w tl zon for the 100-in. eac+v 6 w4rtd (d;1lwl-y2qze(254-$cm$ mirror diameter) Mt. Wilson telescope ($\lambda=550\mathrm{~nm}$)?   $ \times10^{ -5}\;^{\circ}$

  Suppose that you wish to constr,q /c.ld zpsi4bd e+i+uct a telescope that can resolve features 7.0 $km$ across on the Moon, 384,000 $km$ away. You have a 2.0-$m$-focal-length objective lens whose diameter is 11.0 $cm$.
What focal-length eyepiece is needed if your eye can resolve objects 0.10 $mm$ apart at a distance of 25 $cm$? $f_e$ =    cm
What is the resolution limit (radians) set by the size of the objective lens (that is, by diffraction)?
Use $\lambda=550\mathrm{~nm.}$ $\theta$   $ \times10^{ -6}\;rad$

  The normal lens on a 35-mm camera has a focal length of 50.0:qrecwn 2kxe-g .01 ed $mm$. Its aperture diameter varies from a maximum of 25 $mm$ $(f/2)$ to a minimum of 3.0 mm $(f/16)$. Determine the resolution limit set by diffraction for $f/2$ and $f/16$. Specify as the number of lines per millimeter resolved on the film. Take $\lambda=550\mathrm{~nm.}$
For $\frac{f}{2}$ we have $\frac{1}{RP_2}$ =    lines/mm
For $\frac{f}{16}$ we have $\frac{1}{RP_2}$ =    lines/mm

  Two stars 15 light-years awoi;fwecu )75c8hizo * ay are barely resolved by a 55-$cm$ (mirror diameter) telescope. How far apart are the stars? Assume $\lambda=550\mathrm{~nm.}$ and that the resolution is limited by diffraction.   $ \times10^{11 }\;m$

  (a) How far away can a human eyeaju xox yp-8,z p*zft4cqi4 19 distinguish two car headlights 2.0 $m$ apart? Consider only diffraction effects and assume an eye pupil diameter of 5.0 $mm$ and a wavelength of 550 $nm$.
L =    km
(b) What is the minimum angular separation an eye could resolve when viewing two stars, considering only diffraction effects? In reality, it is about of arc. Why is it not equal to your answer in (b)? $\theta$ =    $\times 10^{-3}$ $^{\circ}$

  The Earth and Moon are separat atc cl3.hahe*0+jn3 ved by about $400\times10^6\mathrm{~m.}$ When Mars is $8\times10^{10}\mathrm{~m}$ from Earth, could a person standing on Mars resolve the Earth and its Moon as two separate objects without a telescope? Assume a pupil diameter of 5 $mm$ and $\lambda=550\mathrm{~nm}.$  ----待选择----yesno 

  X-rays of wavelength 0.133 nm fall on a crystaay56-f) / 8nwssvv .y j1mlpaul whose atoms, lying in planes, are spacedyf 1svyv6j8w) asm-l/ 5p.una 0.280 $nm$ apart. At what angle \phi (relative to the surface, Fig. Below) must the X-rays be directed if the first diffraction maximum is to be observed? $\phi $ =    $^{\circ}\,$

  X-rays of wavelength 0.0973 nm are directed at a hwwg8iqls;dt2-)j/ yn unknown crystal. The second diffracwg2i js;qt-lwy 8)d/htion maximum is recorded when the X-rays are directed at an angle of $\mathrm{23.4°}$ relative to the crystal surface. What is the spacing between crystal planes? d =    nm

  First-order Bragg diffraction is observed ata old;p1ey;) c $\mathrm{25.2°}$ related to the crystal surface, with spacing between atoms of 0.24 $nm$.
(a) At what angle will second order be observed? $\phi_2 $=    $^{\circ}\,$
(b) What is the wavelength of the X-rays? $\lambda $ =    nm

  (a) Suppose for a conventional X-7qj yv3 .p/qpvuljbda-- .qj(ray image that the X-ray beam consists of parallel rays. What would be the magnification of the image? a th /p7.v3 qypdj.(qbuvlj--qa je magnification is   
(b) Suppose, instead, the X-rays come from a point source (as in Fig. Below) that is 15 $cm$ in front of a human body 25 $cm$ thick, and the film is pressed against the person’s back. Determine and discuss the range of magnifications that results. $m_1$ =    the magnification is  

  Sam purchases $+3.50-diopter$ eyeglasses which correct his faulty vision to put his near point at 25 $cm$. (Assume he wears the lenses 2.0 $cm$ from his eyes.)
(a) Calculate the focal length of Sam’s glasses.    cm
(b) Calculate Sam’s near point without glasses. his near point is    cm
(c) Pam, who has normal eyes with near point at 25 $cm$, puts on Sam’s glasses. Calculate Pam’s near point with Sam’s glasses on.    cm from her eyes

  As early morning passed toward midday, and the sunlight got more intense, a phovff 6c5b.0y fbtographer noted that, if sheby.c5vff6b 0f kept her shutter speed constant, she had to change the $f$-number from $f/5.6$ to $f/22$. By what factor had the sunlight intensity increased during that time? $I_2$ =    $I_1$

Show that for objects very far away (assume in477zd7lcw alwfinity), the magnification of a camera lens is proportional to its focal lengcw7alzw74ld 7th.

  For a camera equipped witvhe(ogbf*5cu8q2te :h a 50-$mm$-focal-length lens, what is the object distance if the image height equals the object height? How far is the object from the film?
$d_o$ =    mm
d =    mm

  A woman can see clearly with her right eye only when objects are betwuujc4u,:l /a ween 45 $cm$ and 155 $cm$ away. Prescription bifocals should have what powers so that she can see distant objects clearly (upper part) and be able to read a book 25 $cm$ away (lower part) with her right eye? Assume that the glasses will be 2.0 $cm$ from the eye.
$P_1$ =    D(upper part)
$P_2$ =    D(lower part)

  A child has a near point 2032b8za9rg sbs c1f7 w92ilokrd xej of 15 $cm$. What is the maximum magnification the child can obtain using an 8.0-$cm$-focal-length magnifier? What magnification can a normal eye obtain with the same lens? Which person sees more detail?
$M_1$ =    $\times$
$M_2$ =    $\times$

  What is the magnifying powert(sp 7*uynkvy4 ( gs;r of a $+4.0-D$ lens used as a magnifier? Assume a relaxed normal eye. $M$ =    $\times$

  A physicist lost in the mountains tries to ms nme m3cb jo.jx-0pp q91w4m6ake a telescope using the lenses from his reading glasses. They have j4p3e 6.qj cm-ws1pmn 9o mxb0powers of $+2.0-D$ and $+4.0-D$, respectively.
(a) What maximum magnification telescope is possible? $M$ =    $\times$
(b) Which lens should be used as the eyepiece?    D

  A 50-year-old man uses e (kc.urw9l)i $+2.5-diopter$ lenses to read a newspaper 25 $cm$ away. Ten years later, he must hold the paper 35 $cm$ away to see clearly with the same lenses. What power lenses does he need now in order to hold the paper 25 $cm$ away? (Distances are measured from the lens.) $P_2$ = +    D

  Spy planes fly at extremely high alti7euma 6wb8wks*5fq g 7tudes (25 $km$) to avoid interception. Their cameras are reportedly able to discern features as small as 5 $cm$. What must be the minimum aperture of the camera lens to afford this resolution? (Use $\lambda=550\mathrm{~nm}.$)D =    cm

When shooting pictures at very short dz rflc s5wwrfrhdk8a o5.ov- .-0w)0 tistances, exposure times must be increased because of the increased distance of the lens from tzh)k5.8octo05r lsr-w ad-fww. 0vfrhe film for a focused image.
(a) Show that when the object is so close to the camera that the image height equals the object height, the exposure time must be four times longer (or 2 f-stops) than when the object is a long distance away (say, $$\infty), given the same illumination and f-stop.
(b) Show that if $d_o$ is at least four or five times the focal length f of the lens, the exposure time is increased by less than half an f-stop relative to the same object being a great distance away.

  The objective lens and the eyepiece of a tele(k t+xqpt4bs59luba 4t lw0:escope are spaced 85 $cm$ apart. If the eyepiece is $+23$ diopters, what is the total magnification of the telescope? $M$ =    $\times$

  The Hubble Space Telescope, with an objectivebo .bo5 )kat:h diameter of 2.4 m, is viewing the Moon. Estimate the minimum distance be:ko5ah.tob b) tween two objects on the Moon that the Hubble can distinguish. Consider diffraction of light of wavelength 550 nm. Assume the Hubble is near the Earth.    m

  Two converging lenses,fe8snx-zbr : + one with $f=4.0\mathrm{~cm}$ and the other with $f=44\mathrm{~cm}$ are made into a telescope.
(a) What are the length and magnification? Which lens should be the eyepiece?
The distance between the two lenses is   cm
M =    $\times $
f =    cm
(b) Assume these lenses are now combined to make a microscope; if the magnification needs to be $25\times,$ how long would the microscope be?    cm

  An astronomical telescope has a magnification iuj/,hn., oruof 8.0. If the two lenses are 28 $cm$ apart, determine the focal length of each lens.
The focal length of the eyepiece lens is    cm
The focal length of the objective lens is    cm

  You want to design a spy s4+.p v8 (,mq;cv(a/siaiuzojb 6w d gyatellite to photograph license plate numbers. Assuming it i,cidvg8js(ybz6v ua mi qa;(/+o. pw4s necessary to resolve points separated by 5 $cm$ with 550-$nm$ light, and that the satellite orbits at a height of 130 $km$, what minimum lens aperture (diameter) is required? D =    m

  A Lucite planoconvex lens (Fig. Below) has one feiok3+0rh3mfkyv )r5+7 r 4bj7ktt tflat surface and the other has $R=18.4\mathrm{~cm}.$ This lens 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 glass 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? $d_{i\,red}$ =    cm
$d_{i\,orange}$ =    cm