Why is the depth of field greater, and the image sharper, when a camera lhp:9 06 (i 8yxptnnz rsb00zfhens is “stopped down” to ans609np(r0zbtx8if z hpy0: h larger f-number? Ignore diffraction.

Describe how diffraction affects the statement that the depth of field is greateyei .xjrvq k.+3;nd1 er and the image sharper whenn3ij.e;qrxk1 dey.v+ a camera lens is “stopped down” to a larger f-number.

Why must a camera lens be moved farth8jq+rdd7 9b lvdkaf2 5er from the film to focus on a closer objectkraj957dd2bd8+vfq l?

Why are bifocals needed mainly by older persons and not ge f9d-t;mtmpp l5d)rw df(i2rei-pk3 7nerally by younger peopl(d 9;m3tfi2p-pl efd kmp-dr 7 t5)iwre?

  Will a nearsighted person who k.d: lck9j3vb,3ao d gwd6:yr5xdr q(wears corrective lenses in her glasses be able to see clearly underwater 5 , dbgk6xrdjy9(lvcq3r3o : .wdakd: when wearing those glasses?  ----待选择----yesno Use a diagram to show why or why not.

You can tell whether a person is nearsighted or farsi7+jkp m+ aee.x1yam-v5qaxj xic8q7 - ghted by looking at the width of the face through their glasses. If the person’s face apc j78-ea +mxqa.m q+v1 j5ke -axipx7ypears narrower through the glasses (Fig. Below), is the person farsighted or nearsighted?

In attempting to discer5 2h0u87qw9;avm i zm legav1rn distant details, people will sometimes squint. Why does mz;u0a95 qa82igvvwlem 7rh1 this help?

Is the image formed on thlwx+yswdb imzu3tc /c8x/. 4,:po0v p e retina of the human eye upright or inverted? Discuss the implications of this pv 3 p./txl/dsyxi+wm , zu04cw8bco:for our perception of objects.

The human eye is much like a camera — yet, when a camera shuta6;bubien4 e5po v+ y0ter is left open and the camera is moved, the image will be blurred; but when you move your head with your eyes open, you still6b 4; unpy5e+0e obvia see clearly. Explain.

  Reading glasses use converging lenses. A simple magnifier is also a conveodk jjl4nf:* *rging lens. Are reading glasses tj l*n4*f:ojd kherefore magnifiers? ----待选择----yesno  Discuss the similarities and differences between converging lenses as used for these two different purposes.

Inexpensive microscopes for children’s use usually produce images that are colol(- m..q d i:kna-nidhred at the edges. W ndn- h.m( d:ai-.liqkhy?

Spherical aberration in a thin lens is minimized if ra 7yaz gah qem4ntf;s*/y +-vf7ys are bent equally by the two surfaces. If a planoconvex lens is used to form a real image of an of4m;e +y/7hta*yf- v nzqs7agbject at infinity, which surface should face the object? Use ray diagrams to show why.

Which aberrations present in 5qs*h* cor :o7cql7y oa simple lens are not present (or are greatly reduced) in thr*qh s*oc7:cq7l yo 5oe human eye?

Explain why chromatic aberration occurs for thin lenses but 3pp k(6n(up9t4 1gmdfp0bxpg 2hbu z0 not for mirrors.

  By what factor can you improve resolution,(w 24gqwio(nn other things being equal, if you use bl2q4((gwi wonn ue light ($\lambda=450mm$) rather than red (700 $nm$)?  

Give at least two advantages for the use of large reflectingqc/.d1+xa1qu v axr+a mirrors in astronomd uxaq qax+/1vr ca.+1ical telescopes.

Which color of visible light would give thep fvf(w67sq t5 best resolution in a microscope? Explain.p7v(6s tfwf5 q

  Atoms have diameters of acrqlvo4c/t1.+pu:r q4whv- about $10^{-8}\,$cm$. Can visible light be used to “see” an atom? ----待选择----yesno  Explain.

  A 55-mm-focal-length lens hyn*pg.)8e* vle /yaqcas 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 lpj(td zvg3m- 6ksgp73ens 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 camesh(vg4x xt.-ch2,o bgra 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 iubq.dbhzkl/( m 8p.n 6s 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 abmabob 08 m30ndjusted so that it is 200.0 mm to 206.0 mm from the f00 maobn8b3 mbilm. For what range of object distances can it be adjusted?    $\mathrm{m}\leq d_{\circ}\leq\infty$

  A nature photographer wishes to photograph a 28-mtall tree fromu 3ot ulc09 ri/doxja3a0a+r+ x8rs.x a distance of 58 m. What focal-length lens should be used if the image is to fill the 24-mm height of thea+ra0x lu+ 9x o0cr8/ tds 3axoijr3.u film?    mm

A “pinhole” camera uses a tiny pinhole instead loqg)m x1*m(arh3 58+yt pnhdof a lens. Show, using ray diagrams, how reasonably sharp images can be formed using such a pinhole camera. In particular, consider two point oba 5h)m(od13q*ypg n8 hml rt+xjects 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 il2b *z,axr2ie a 6t 7hbav9: bihh5gk6s $\frac{1}{250}\,s$ 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 abjm :jrqn r,0.:efx3 t huodh*9out 2.0 $cm$ 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 f5m l-5mch,h0mq1*aewz fup /for the far pau-hmhq mzc/me,0ff55lp *1 w oint $(=\,\infty)$ 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 neededj / uaa:3h9n;lx4d y*mcv/z cl 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 of 145z2 xaf1i g)o 38aihbr $cm$. 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 rihdzi2/hidv;+ 10ct0zx;jc l .2v iyiead by holding a book at arm’s length, 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 corrected by amcg5 yyg40 vb0 $-3.50-diopter$ 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 objects cz bjf oflown34:7es, 7learly 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 nearsighted eye in Example 25–6 than thjxd y 1.yz;afvgi4g)/e 2.0 $cm$ of a normal eye?    cm

  One lens of a nearsighted perb+lnv) a9 +;qci4rpa su,e+5ddmlh - gson’s eyeglasses 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–le0z r1t6.w 8ixk mzp+br2la9 cqns system when viewing an object
(a) at infinity,    cm
(b) 33 $cm$ from the eye? Assume that the lens–retina distance is 2.0 $cm$.   cm

  A nearsighted person hd 0gb gvh5sx5fvd f(n:9c.+lfas near 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 use a):kh bh68ehgd with a relaxed eye if its focal length is 12 bhag8hh ke:6)$cm$? =    $\times$

  What is the focal length of a magnifying glassl5icxvdkyhju d801c7ks9 76i of $3.5\times$ magnification for a relaxed normal eye?    cm

  A magnifier is rated at f(g+ (dbeyw3y$2.5\times$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 us13m m5fkoushni8bq- -ing a 9.00-$cm$-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.2,vzdngfn k5o5dzkgx63m .n with a 9.50-$cm$-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 plazj;ekhz m mgb 2 ya-vp429 1)mk;:rjyzced 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 le zi86tcbogsuc o+vh:2 x+yb92 ngth of 8.5 $cm$ 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 w)yp8 qi 3etv+7ix ,9o g)icdxrated 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 astronomica 2tnk l n4+wmz0sfh./yl telescope whose objective lens has a focalkt40h2/ nzf.+nyw slm 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 telescope is desired to be nzwon 30t90dn/mw+gv 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 objective with focal li1;n exr,lu5 oength 85 $cm$ and a $+35-D$ eyepiece. What is the total magnification? =    $\times$

  An astronomical telescope has its two lentq 0cs j (2dzs(np(gx0ai7c:y ses spaced 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 relaxed eya: dyyg (p-5di1e5dnke 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 astron bkxp )3ttup z+/(lm3yomical telescope using a reflecting mirror whose radi3+lzpx) tu( k3mbpt/yus of curvature is 6.0 $m$ and an eyepiece whose focal length is 3.2 $cm$? =    $\times$

  The Moon’s image appears va 8l*8cen,zm.c.o zo))oitr to be magnified 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) has7f, p0mgafj5o:ktk/ p a radius of curvature of 3.0 m for its objec0 7,tmf:ko5p j/fpgak tive mirror and a radius of curvature 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 eyepiece with a focal lengthymw h*ni:f9p/ 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 17ejo ..sy h1zvzlm; r32.0$times$ 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.q5yo3/p.omq4vfjot5 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 assuming that the final image is locatk6exrt(akn.tsx szrb8sh .9/6; ew .n ed 25 $cm$ from the eyepiece (near point of a normal eye). $d_{oo}$ =    cm   $times$

  The eyepiece of a compound microscvmauwvv t 46.hb ,4d3kope has a focal length of 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, placed in contact, that-o.g)1mqk6 d rhcb q7awr: 8yt have foca 8ctwy 7km-rbqrq):16.ohd agl lengths 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 *dbp3ggx.b fz)+ q6qb fi6)rnparticular situation. A planoconvex lens of index of refraction 1.50 and radius of ffb))r6 b.b+ng6d* q3ipgz xqcurvature $R=12.0\mathrm{~$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 resolutio02ubsz uws/ h/n limit (degrees) set by diffraction for the 100-in. (2su0hb/wu2z/s 54-$cm$ mirror diameter) Mt. Wilson telescope ($\lambda=550\mathrm{~nm}$)?   $ \times10^{ -5}\;^{\circ}$

  Suppose that you wish to construct a telescope tha b :olp274exjt1x(cw et 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 hasr rvm ,b/j3.gn a focal length of 50.0 $mm$. 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-y,nvbzo,a2.oj ears away 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 humascp o3r*5jo ra l;ha(-n eye 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 ghplb rse;g/m,si*--9plqy ;separated 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 crystal whose atoms, l0iubjy ,pe gqp/*gr* 1ying in planes, are spaced/0pg1p q ui,ejbgr*y* 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.*yweyk ktvm7 ;t(n5ino, 6gl3f;c or jq3n,j +0973 nm are directed at an unknown crystal. The second diffraction maximum is recorded when the X-rays are directed yfo6,j i(5r*ljn y cmt o,7;nkn+ egq;kv 3w3tat an angle of $\mathrm{23.4°}$ relative to the crystal surface. What is the spacing between crystal planes? d =    nm

  First-order Bragg diffract+fzwspq 0 /w;djny x2)ion is observed at $\mathrm{25.2°}$ 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-ray image that the X-ray b*-f 2b-fdg-jr: ;w afslnm, pseam consists of parallel rays. What would be t -,jfd-naslw ;*m-:brpfs fg2he magnification of the image? a the 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 9m0 lni gbip3/amgjhktvvu s//d-**5got more intense, a photographer noted that, jmugt dihvp9-n*m /iv0/s*53g lka/b if she 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 ( opx(xcgt9)/xb)ezz7pg(te hy )kz: infinity), the magnification of a camera lens is pr(:gg( t)7 )zc/ z)zot9xepkbxyxehp( oportional to its focal length.

  For a camera equipped wn6j v ,o3)oy-sik7b eoith 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 -ty3nrsrti3k - n 1pg3with her right eye only when objects are between 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 of 15orz.c nm ys0 vca3tce336wwm(x c33 .w $cm$. 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 magnifyiny 4 b1tlx (bb2f;o1titq-.ezw g power 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 mab m(-rgbuds)owf ( k77jbs8;dke a telescope using the lenses from his read(7sd- 78( j;kbrbsgu)w ofbmding glasses. They have powers 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)4qitb t.x aot50 -cv.6c)kukt0k2yjw l(r mp $+2.5-diopter$ 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 altit6i2kuws vt6-z udes (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 distances, exposure times must be increasd aw+yfsk,7+q, :s p ,ibzn9zoed because of the increased diy+sno,+ksb p, :z afwz9,q 7distance of the lens from the 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 euxl ue2+m,b- telescope 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 objective diamm 1 -uloua;6uceter of 2.4 m, is viewing the Moon. Estimate the minimum distance between two objects on the Moon that the Hubble can distinguish. Consider diffractioalu6ucm- ; 1uon of light of wavelength 550 nm. Assume the Hubble is near the Earth.    m

  Two converging lenses,t18h9 9id qr u/vekub- 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 of 8.0. If the two lemy+)b9o( lprn 65-7csny9nuc vsma3dnses 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 satellite to photograph license plate numbers. Assuminut:a6;e4ikjb7 ,1sxlf5kgsh dc2e ml/ zm.(t g it is necessary to resolve points s7mdjbf xi(e; s.1/ kl s,4 m2u6l 5ckhetta:zgeparated 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 flat surfabm *86r3)/i tpm* 8atwhdrsbfce 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