Why is the depth of field greater, and the image sharper, when a camije8.eajlj5h .q/t6 fxzm, c8 era lens is “st8c j. .eqjxmh,ai86ejf/ 5z ltopped down” to a larger f-number? Ignore diffraction.

Describe how diffraction affects the statement that the deptlq9xr/ qrhw10xv;8e e 03n bfkh of field is greater and the image sharper when a camera lens is “stopped down” tov9/ 8ehk0qr wqf1nle3;b 0rxx a larger f-number.

Why must a camera lens be moved farther from the film to focus on a closerj vw5ne7n72 mzqg9r 6zj:ccv: objecz59v67j czem r 7gn2qvwcn: :jt?

Why are bifocals needed mhte66 fm. p7ry j wwjo/:2ul9hainly by older persons and not generally by younger peopl .fwomw29tj h yp:/ruje6h7l6e?

  Will a nearsighted person who wears corrective l0 /z(yc;40vv jwfsss fenses in her glasses be able to see clearly underwater when wearing those gla0 (v/v0ffszycw ssj4; sses?  ----待选择----yesno Use a diagram to show why or why not.

You can tell whether a person is nearsighted or farsighm;(g )9mpz4)e)raekp lb pdx2ted 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 person farsigh)ldpg94 prz a;mm 2(ke)x)pb eted or nearsighted?

In attempting to dis6 v))slkgajnqwz6 9e (cern distant details, people will sometimes squint. Why does thiqkgls 6n)j)9w6aez (v s help?

Is the image formed on the retinafguw frg5r7i7 h,w n2. of the human eye upright or inverted? Discuss the implications of this for our perceprf, r i .fn7h7wwu25ggtion of objects.

The human eye is much like a camera — yet, when a camera shutter ivw8)gcs ..ju o29dikvs left open and the camera is moved, the image will be vk.svc98 2) wg.i ojdublurred; but when you move your head with your eyes open, you still see clearly. Explain.

  Reading glasses use converging lenses. A simpl5d.aedhr i,;q u,4bqy e magnifier is also a converging lens. Are reading glasses therefore magq.d, h;4abdi,qy5ue rnifiers? ----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 areil-3 gtsnbd+ 8 colored a38+bndi tl- sgt the edges. Why?

Spherical aberration in a thin lens is minimized if rays are bent equally bzf;nl p;7h h6ay the two surfaces. If a planoconvex lens is used to form a real image of an object atnlha zh6;;p7f infinity, which surface should face the object? Use ray diagrams to show why.

Which aberrations present in a simple lendy6gm,mst (j( 5q 5yjps are not present (or are greatly reduced) m g6(,j5yspmtqj d(y 5in the human eye?

Explain why chromatic aberration occurs for thin lz a)p-2f vrp1fenses but not for mirrors.

  By what factor can you improve resolution, otc 3tx4cj-cc.z her things being equal, if you use blue light zxc-4c c.jct3($\lambda=450mm$) rather than red (700 $nm$)?  

Give at least two advantages for the use of large reflectingwr4sns:6 7crh) d0jh r..qo(s-lq+ w3aehe rr mirrors in astronom6 r jrchh w0lo+4 nw.aeq-.q(:sds 7 )hr3ersrical telescopes.

Which color of visible light would give tu,huqwovshw hin0b /v4i/ rj *w9 as,y1 t20,ihe best resolution in a microscope? Explain.a/hio uw0,nvv ys,w4wq1j,9s h i2bt*0u/hi r

  Atoms have diameters of about-7xe+x: fwb/p)agxdw i7 7q ft $10^{-8}\,$cm$. Can visible light be used to “see” an atom? ----待选择----yesno  Explain.

  A 55-mm-focal-length lens has f-stops +bzf6:+tzw j t 1r:tbfsib7z5ranging 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 lenu wf9r(z3oy2 fp u2r0us 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 camera setting on;hok/v m(5qyf $\frac{1}{250}\,s$ 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 taken ,gz;*)ya 4d. r8 stu)zmxprki 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 adjusted so that it is 200.0 mm to 206.0 m*gksf6; +x1idae0 cs7:h (pzvzp8idm m from the film. For what range of object distances0dmhe6kpdgi pf8: ax;vs1 c (7+i*zzs can it be adjusted?    $\mathrm{m}\leq d_{\circ}\leq\infty$

  A nature photographer wishes to photograph a 28-mtall tree from a distance of 1e2+) uv5w wholg0eik 58 m. What focal-length lens should bv+i1wu02wkel gh ) 5eoe used if the image is to fill the 24-mm height of the film?    mm

A “pinhole” camera uses a tiny pinhole instead o -cf 7xvdj12r96 91,ybqwjka uqokho ,f a lens. Show, using ray diagrams, how reasonably sharp imagec 1d7j vkryxhb9q1kq 2,-jof,aowu 69s can be formed using such a pinhole camera. In particular, consider 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 correctru,q6/ s*d3+jkrc txjy - p-rv exposure is $\frac{1}{250}\,s$ 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 abou+bdgl.: yd5/( wdxhd;nb29yuf yvd h2 t 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 len rzbitb.bg (;55jgpg7 ses corrected for the far poin5z5g (7gbi.gj ;prtbbt $(=\,\infty)$ 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 tf +*/ic/q d h,felv( hgi61ueare needed 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 poisbj,-j yi2zv(0zt lf7 nt of 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 boo cs3v2)6c t2qao3i z,mpzue1(e, qb myk 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 il3 f/o /- dvgqp,b-8eds+n 1 s q3dszui6mzp8zs corrected 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 objects clearly only if they are bea)8.k tl 9regw kz22-;rh)rweahyio;tween 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 t *hilcy( n/ps0han the 2.0 $cm$ of a normal eye?    cm

  One lens of a nearsigeg9e ,shlk5:c:(sly vz.t j /fhted person’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 obvy/dabr 985mf the eye–lens 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 has near and far points of ( tim pcb.8zs1fh.w0k 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 relaxed eye if its fot +6vqt1fw* u+dri kf-ao)b5n cal length isitdf*qvrbo+ 5 1nt -6)ka+fwu 12 $cm$? =    $\times$

  What is the focal length of 4zk1b;8fvgrm(ag q2 c a magnifying glass of $3.5\times$ magnification for a relaxed normal eye?    cm

  A magnifier is rated n/ue wp7nxt 09x6c2qk4fkx5 e at $2.5\times$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 a5iz 3 j;,xvscbt hcrm0-f .*ru 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 viewedith xs q9+ear v91ba;snav yi3 ,..mr: 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 placedygowg0h m1;h2 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 len q9v:*yezim-: udmgj7gth 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 itb/kx6 *2l5 . mxsd ly4)eela1ff-hmr s 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 telw8arom 5i7ck; o+r9u)v2oj;wwyrji3escope whose objective lens has a focal ov2roi 9o)35uwwkr; +a jjy 7w;ric8 mlength 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 astruli ql;6.e jp;2c*pz qonomical telescope 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 objective pf-uxb,/94 lh8wevt rwith focal length 85 $cm$ and a $+35-D$ eyepiece. What is the total magnification? =    $\times$

  An astronomical telescope has its two lenses spax5uo;7 8u.q bl xrxs,iced 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 forsq0rdg6 4 ( vl xz(qh5gv2fs)o a relaxed 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 asty . trkt.bh; ov zze-q0f*-m3pronomical telescope using a reflecting mirror whose radius of curva. 3e *of0zt;hybzp r .m-vtqk-ture is 6.0 $m$ and an eyepiece whose focal length is 3.2 $cm$? =    $\times$

  The Moon’s image appe u3bn0/pwlvd0nht 51ears 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) has ot9ri */l,2hg g f.k l (is3f.woahua0a radius of curvature of 3.0 m for its objective mirror and a .i/2w0 s rk,hl.o *ot3aau9h( ligf gfradius 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 w4ym ,wquu0hme s5- 8 zz6bb(dtith 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 12.0xrgx 2ge6xe)/$times$ 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 1.8)p -u5xk ku9yb-$cm$-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 i r/nrq 3q 57ul9mbjsp+kt:cf9s 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 of 2.70h w q1hk. oeps. s xv+-ixfy:q/,4k2xn $cm$, 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-1y yhmn t j)vzx(32td-zn8f v, that have fo31vy8hntn yv-tfj dzzx)m -( 2cal 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 particular situation. A pla7. yp)jx3 l *u3mllqkknoconvex lens of index oulqjym*.p l )xl73k k3f refraction 1.50 and radius of curvature $R=12.0\mathrm{~$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 resolutio+*dm9hm p rat;n limit (degrees) set by diffraction for the 100-in. ;d+pmhr*m9 at (254-$cm$ mirror diameter) Mt. Wilson telescope ($\lambda=550\mathrm{~nm}$)?   $ \times10^{ -5}\;^{\circ}$

  Suppose that you wish to construct a telescope that can resolve featuntb+i5u9ghnue : :,o.da2yv pres 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 50.0l0 w;ek :q).dmfm;7gflt1kso:w5oq v $mm$. 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-yj*,z rtx-li/p 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 human eye distinguish two car headlightsve5q-j l+b)cxd p)u.d 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 sepa/ 6er7buzq f(hf7i8u:n axdkw 0dx s)9rated 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, lying in w-)9kwx; xgya9uuxd+ planes, are spaced)gd9x+ way9-xx u;kwu 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 h31 qx(g i2ptodirected at an unknown crystal. The second diffraction m(qp1gix2 ho 3taximum 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 difq upukr. iw8w*q70gg1 fraction 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 beam consisqptmj29rt(go z1i 8.o-m c2yk ts of parallel rays. What would be the magnification of the image? iq9tprj-28o. (com1gt zkym2a 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 got more intense, a ph9 l3ohe7:q noc fw pk00y75xthotographerpt07w c9hoko0357n: xheqlyf noted that, 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 infinity), the magnification of :1nf t(9 pcevr-bl4zgf+ pl 4qa camera lens is proportional to its focal length.4l1q 4plp+9 :-ff (rbvzn gcte

  For a camera equipped with a 50- bb+ :n j:m.jx-a-zmpl$mm$-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 between 5m+qbv/na pbxaa 8( pzp ee:3.45 $cm$ 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 poq*pqda,u h0( xint 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 power qu8aj - xnn;sg5l4 y2fof a $+4.0-D$ lens used as a magnifier? Assume a relaxed normal eye. $M$ =    $\times$

  A physicist lost in the mountains tries to make a telu ( 6zqegxr7 -/uwbv,aescope using the lenses from his reading glasses. T-ru ,wv7uqxg(6a/b ez hey 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 ; jz.w 7.3ty-*bne du ny1pquk$+2.5-diopter$ 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 extzd 9 bxrm23wa*co7er/remely high altitudes (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 increas*0gw 4vz txzu/uyt.+sed because of the increased dis4tuy*vw./ + zgztxu 0stance 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 telescope j,;sx+qp js;j +vd(4zuvuc 5e 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 diameter of 2.xrb2vpn)j :b ;4 m, is viewing the Moon. Estimate the minimum distance between two objects on the Moon that the Hubble can distinguish. Consirb;jxv) bp:2nder diffraction of light of wavelength 550 nm. Assume the Hubble is near the Earth.    m

  Two converging lenses, one wrwo pbz*iv3hd 92zalj2 np536 ith $f=4.0\mathrm{~cm}$ 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 8.0kvy-m)wc)sr8e0 k pp6. 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 aujw gr6 /59d:8rf)jknv(mu 09r st qla spy satellite to photograph license plate numbers. Assuming it is necessary to resolve points separarrv06mr j:atwn fl()sju/9g 5q8kud9ted 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 surface and(ngx)(lh3g xs 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