Why is the depth of field greater, and the image sharper, when a camera lens is3 rjkqkd-2qid/ 20 1 5unplt cev+u)ql “stopped down” to a larger f-number? Ignore diffraction.5r2+q ldje3v /0-iu)kq pd1tu2k lnqc

Describe how diffraction affecto :au7fmy40krtq7 rvc6ww g*9s the statement that the depth of field is greater and the0wgq tya7*um vow97rr: 4kc6f image sharper when a camera lens is “stopped down” to a larger f-number.

Why must a camera lens be moved farther from the film to focus on a closer5 )ic8r)icq ln object8 ccni5) irl)q?

Why are bifocals needed mainly by olde ne(34jmazlz* hn)v)y :g/uzzr persons and not generally by younger peo)z3/e lj: *uaynhgz4z(n)mv zple?

  Will a nearsighted person who ,)w:lwf7g ogsx/ p) wj:)9hc kg3xjjowears corrective lenses in her glasses be able to see clearly underwater when g,spx k39f w/:j hx)wcg:wl)jj 7g)oowearing those glasses?  ----待选择----yesno Use a diagram to show why or why not.

You can tell whether a person is nearsighted or farsighted by looking at the x z2nfe9aiv/jab/, az e6*2ayr*(gtvwidth of the face through thei9 jr2v, *a*izfnexv6ta (aey2a// bgzr glasses. If the person’s face appears narrower through the glasses (Fig. Below), is the person farsighted or nearsighted?

In attempting to discern distant details, people will sometimes squint. hu5u- ty ax,6/z(/pe+ pcces*tebf t0Why does px5e,+ (t/c0tc6h yefue-p/abus*tzthis help?

Is the image formed on the retin)ykrhum qrit i3(8 5)fa of the human eye upright or inverted? Discuss the implications of this for our perception of o(5)f 8qmk)rr3tyhi iubjects.

The human eye is much like a camera — ye6 gzvl3c:)45f nigvig t, when a camera shutter is left open and the camera is moved, the image will be blurred; but when you move your head with your eyes open, you still see cleazlvg:4 c gfi3 n5)ig6vrly. Explain.

  Reading glasses use converging lenses. A simple magnifier is also a conv.(6 gu:0jsun)(cgk gaphu cj+ erging lens. Are reading glasses therefore mag. j)gc0k (s(hupu6g c+aju:gnnifiers? ----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 e*c7:hk8sl7qvcbe2b z q *v-g images that are colored at the edges. W hg b-bczq27:vvekl e8*s*q 7chy?

Spherical aberration in a thin lens is minimized if razih j9 nfzsf,2uh x/9p7c+ pp4ys are bent equally by the two surfaces. If a planoconvex lens is used to form a real image of an object at infif2p9 jh+h,usz7i9nxp c/ 4 zfpnity, which surface should face the object? Use ray diagrams to show why.

Which aberrations present in a simple lens are not present (or are grean7b -2r/dt)uhuk+ hfz tly reduced) in the human eh )z2uh- u+r7ktd /fbnye?

Explain why chromatic aberration occurs for thin lenses butuin/l 5dwkr(qe/6 hp ;+ phf)y not for mirrors.

  By what factor can you im c cd.mi20g ,4v/bmmumprove resolution, other things being equal, if you use blg/0dm4bmci,c.mm u 2v ue light ($\lambda=450mm$) rather than red (700 $nm$)?  

Give at least two advanfth3faaqohp7m 8m6;av xi6 zb33m93a tages for the use of large reflecting mirrors in astronomicalf 8 aqbm363xz hm 6v7paaoma93hfit; 3 telescopes.

Which color of visible light would give the best res:r 2h q zffy0cf/6fng4olution in a microscope? Explainzcf:f2h 6 rf qygf/04n.

  Atoms have diameters of aboubd 84k)(f uq row;9pkqt $10^{-8}\,$cm$. Can visible light be used to “see” an atom? ----待选择----yesno  Explain.

  A 55-mm-focal-length lens has f-stops ranging fr;f 5qbp y)t1ee*pmxh mz+s9k(om $f/1.4$ to $f/22$. What is the corresponding range of lens diaphragm diameters?    $\mathrm{mm}\leq D\leq$    $\mathrm{mm}$

  A television camera lens has a 1 q 3-4j pgx*ftuqm:3a9vlh7 ly4-$cm$ focal length and a lens diameter of 6.0 $cm$. What is its $f$-number? $f$/  

  A light meter reports that a camera setting ofvw2wsxp ce8 v:(7 i fy.jb2;nr $\frac{1}{250}\,s$ 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 photogra4ogi: dri 1nl9b mxx27ph is 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 lf)iv4u.3j9udgc xt;p:sm 8 ixkh,r 4b ens can be adjusted so that it is 200.0 mm to 206.0 mm from the film. For what range of object distan k:h 34c ,ui9.usjbvdpx)fx;tmi8rg4 ces can it be adjusted?    $\mathrm{m}\leq d_{\circ}\leq\infty$

  A nature photographer wishes to photograph a 28-mtall tree from a distance ofmt j g4e*9t3nn 58 m. What focal-lengtm4g*9j3 ntne th lens should be used if the image is to fill the 24-mm height of the film?    mm

A “pinhole” camera uses a tiny pinhole instead77cle3ti b6+wbn sj -ek (ni-fz 04sus of a lens. Show, using ray diagrams, how reasoe+-fsbc i6u 0bj -3lk s7se7wnti 4z(nnably sharp images 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 correct exposursea bo+ o04hg luc.(p1e 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 about 2.0 w6 gzs/a7gmk3,h v4cp $cm$ 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 worw9aj0d7lx 9zab ni5zwzq++ 5i8 ; jhjae contact lenses corrected for the f0h5+5dql z zn wiazw+;xai 97jja9b8 jar point $(=\,\infty)$ 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 needed for a person whose tb/8ix2dcm3n,gq j)b 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 n9ln6asq g w9;zz1p u gt*+5slof 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 9n7; zfr wz,igbook 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 iw,s vso + /dd9p3i+yjps 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 apihlj5. 7of8xpg0+km re 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 rqq0r0f /2 4m1rmo+vmnj5k mk Example 25–6 than the 2.0 $cm$ of a normal eye?    cm

  One lens of a nearsight/muv8o ff d.l:ed 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 of the eye–lens system when viewinps;6 od n -nj0snol4/l76hulniozr3 -g 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 (ye3:ru,s h hsof 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 u keax7l564*vq n 1+dct adnh7nsed with a relaxed eye if its focal length i*ed4v6t a7lh xn +nq1dkacn 57s 12 $cm$? =    $\times$

  What is the focal length of a magdsk z dem2tjm4:ar/dnx )n53 0nifying glass of $3.5\times$ magnification for a relaxed normal eye?    cm

  A magnifier is rated at.)qggp7o i0 kgjxd/ ctwh :8/o $2.5\times$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 usi5 vnt(mr:re/4n-s pl kng 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 view3l eso3+ otrt *foxpv- u)1b)ced 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 placek,qrd p/ig 9xcb+5741 s mdfapd 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 ofihzse3 4cuu07 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 rate6.n ri-o,fr yad 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 magnific 2*lx;tug azjsnn3;6of i8q7l ic:t *mation of an astronomical telescope whose objective lens has a focal lejstlcg:n lf m; *izt86*3 ;q 7naxui2ongth 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 5(kyt8kcj 0t sdcvn7825$\times$. 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 length 8yl(xfxhx/5 r 25 $cm$ and a $+35-D$ eyepiece. What is the total magnification? =    $\times$

  An astronomical telescope has its to (3bs;e pa5uuwo lenses 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 adj;7 ur5kgo)6 :*-joujuh/e muq( kj xiuusted for 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 astronomical telescope using a ret3 oy7u6up /bf:gu8ea flecting mirror whose radius of curvature is ou78g 63tbua:yeu fp/6.0 $m$ and an eyepiece whose focal length is 3.2 $cm$? =    $\times$

  The Moon’s image appearsd-lwa2rysmm3/*g nj9-z 0ge w 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. Belowgl0s- mmz;xe93ef4jc ) has a radius of curvature of 3.0 m for its objective mif xse3mmj ;g4ec9z0l-rror 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 length (.j.;9 7jy-u2)ecoo dir u sslo+b euoof 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.y*sxt/sk )bo* -ehm7n0$times$ 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 1.8dl33i+:7; ao yppmfyr-$cm$-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 located fe mj+ uz(xz), tlf0xsu6 :6nz25 $cm$ from the eyepiece (near point of a normal eye). $d_{oo}$ =    cm   $times$

  The eyepiece of a compound microscopwr kdmx::(3yqe 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 thixkej 2e 38 ;i8wwflagi a4e,p;n lenses, placed in contact, that have k,aigxi8 e4l32w f;w;p aeej8focal 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 sitcx l.ofe4*+s k4lxv *guation. A planoconvex lens of is*4kxe+ xgll4*fvo. cndex of 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 resolution limit (degrees) set by diffraction for the 10 ijgjo2cyb ,u4u(pl:ci qm3 000-in. c pii0m(j:lu 3o4c2q,yubj 0g (254-$cm$ mirror diameter) Mt. Wilson telescope ($\lambda=550\mathrm{~nm}$)?   $ \times10^{ -5}\;^{\circ}$

  Suppose that you wish to constrc85dh .avg0f quct 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 5/ ard-g .*ge,rev (iks0.0 $mm$. 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-years away are barely resol7t jydpelz. g4e+8f3 nved 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 ey0ppd 8x 8ci6rce 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 separj1yc1prh7.l+f. wg:x zfr on3ated 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 atoms9 d mgv432 tp;q4kfnmww8vph,mxu)/h , lying in planes, are spaced 0.280 /hp4q 43fngpv 9,m)m t 8mvkh;2w xudw$nm$ 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 0.0gr: q-l2 6 sv*bcnl6wk973 nm are directed at an unknown crystal. The second diffraction maximum is recorded*lcrlq6vn:wb6ks- 2 g 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 diffractioqh*)x9*3 ihr8 ,gpgj/ 6nlmpfcf a-d hn 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-rai9i* o f2+sbjce:a (h)q)zjfby image that the X-ray beam consists of parallel rays. Whe )*:) j(ca sfi2fhqob ibz+9jat would be the 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 qln, ;;pfs6w xsunlight got more intense, a photographer noted that, if she 6qw;n;l, px sfkept 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 infinity3; ;kq2pnyd e*eccl in0zxd*-x o 0j0z), the magnification of a camera lens is proportional to its focal lengtl3c; jzxc0nq-i2oz;p x dy*n0kede0*h.

  For a camera equipped withw,r3kv .hfn2 ch.s4mw2pc1sy 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 a)k64zlg kowf6)ke *v6w,v yrq *bllk1 re 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 poi9i7gkt7swiqr(/xd )2ubf,h i nt 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 of ap**zx(x qic3 5qd4wa s $+4.0-D$ lens used as a magnifier? Assume a relaxed normal eye. $M$ =    $\times$

  A physicist lost in the mountains triesdxq,. ,fvy ;f4ob1 els to make a telescope using the lenses from his reading glasses.xy1.4 s lf,v,;qfodbe 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 t02mkcpj;6vd1hn q.z $+2.5-diopter$ 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 altitudes5meaz1vhdig csucd28c* ; ; o0 (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 ti2czsk/16j ksc lw6yjhli9* v/mes must be increased because of the increased distance of the lens f/s1 wv klc6iyc jlkh6sj z2/*9rom 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 are s2xl z3s1tck*bpaced 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 2.4 m, is vi.n+7d4ofjr f rewing the Moon. Estimate the minimum distance between two objects on the Moon that the Hubble can disfr.nr4 o d7+fjtinguish. Consider diffraction of light of wavelength 550 nm. Assume the Hubble is near the Earth.    m

  Two converging lenses, ok x/ 9vkhd: fnmw/m-k,ne 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 8c 2v lzt2 7qtgos8v-8 /ilnxumagnification of 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 satellite toet66r-.shgt r photograph license plate numbers. Assuming it is-r6sh tge 6.tr 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 flat snvp9 z f72cj(l.6bybeurface 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