DO NOT OPEN THIS EXAM UNTIL TOLD TO DO SO.

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1 Exam 4.00 COMPREHENSIVE EXAM 7 May 2003 General Pysics II (PHSX 2020) Adam Jonston DO NOT OPEN THIS EXAM UNTIL TOLD TO DO SO. MAKE SURE TO PUT YOUR NAME AND SEAT NUMBER ON THE FIRST PAGE OF THE EXAM BEFORE YOU TURN IT IN. EQUATIONS AND CONSTANTS CAN BE FOUND ON THE BACK OF THIS COVER PAGE. Advice/Info: Tis is not just a pysics exam it is a playful dance wit te natural world to see wat it will allow you to reveal. If you ave learned anyting tese last few weeks it sould be tat you as a member of umanity ave te ability to understand te natural world. Enjoy and celebrate tis ability. Sow your work clearly; for tis will make bot Moter Nature and (more importantly) your grader appy. Ask questions if you ave tem. Take a deep breat. Double ceck tat your answers ave been circled and tat everyting is appropriately labeled. Sarpen your pencil. Inale. Exale. Good job. On tis exam te universe is very simple so you can ignore tings suc as air resistance resistance of conducting wires te effects of air on te speed of ligt and te gravitational field of te person sitting next to you. Have a great summer and beyond keep in touc. You sould ave five (5) pages in tis exam not including tis cover seet. (Pages are copied front-back so you only ave 3 pieces of paper in addition to te cover seet.) 50 points are possible. Relax. Tis is it. You may never ave to take pysics ever again (well tat depends on ow you do on tis exam I guess) but you will always ave to deal wit pysics. Tis exam sould be a piece of cake compared to te rest of your life. Savor te experience. Tarzan wasn t a ladies man He d just come along and scoop em up under is arm Like tat quick as a cat in te jungle But Clark Kent now tere was a real gent He would not be caugt sittin around in no Junglescape dumb as an ape doing noting Superman never made any money For saving te world from Solomon Grundy And sometimes I despair te world will never see Anoter man like im Hey Bob Supe ad a straigt job Even toug e could ave smased troug any bank In te United States e ad te strengt but e would not Folks said is family were all dead Teir planet crumbled but Superman e forced imself To carry on forget Krypton and keep going Tarzan was king of te jungle and Lord over all te apes But e could ardly string togeter four words: I Tarzan You Jane. Sometimes wen Supe was stopping crimes I ll bet tat e was tempted to just quit and turn is back On man join Tarzan in te forest But e stayed in te city and kept on canging clotes In dirty old poneboots till is work was troug And noting to do but go on ome Brad Roberts

2 General Formulae: KE = 2 mv 2 Fnet = ma ac = v2 r P= p = mv E t I= P A A =!r 2 s = r! Specific Formulae: F=k q q 2 r2 E=k Q r2 2 Q = CV E = 2 QV = 2 CV P = IV RS = R + R2 + R3 +L C P = C + C2 + C3 +L I = Q/t V = IR R P = R + R2 + R3 +L V = V0 e! t / RC F = IlB sin! c= m = 3.00! 08 s " 0 µ0 # m" d sin! = $ %(m + 2 )" "V "s CS = C + C2 + C3 +L F = qvb sin! V = " (! e! t / RC ) E=! µ0 I B=N 2R I Avg = c! 0 E 0 2 =!= 22. " D! = BA cos "! = " N #$ #t c B0 2 µ0 I = I 0 cos 2! n sin! = n2 sin! 2 sin! c = n2 / n + = d o di f! = m=! di i = d o o v2 " 2 c p =!mu E = f!t = "!t 0 E =!mc 2 KE emax = f! BE Ln = mv n rn = n 2! L = l( l + ) L L= 0! E 0 = mc 2 2! n2 rn = ab Z LZ = ml 2!!= p En =! " m% n!pase total =!pase pat +!pase reflection = # $(m + 2 )% n v + u' vu' + 2 c KE = ("! )mc 2 u= (!x )(!p) " Z2 (3.6 ev) n2 E = (!m)c 2 Constants and conversions: qe = C k = N m2 / C2!obs =! s 4# + u / c " u / c E 2 = ( pc) 2 + (mc 2 ) 2 (!E )(!t ) " 4# # & = R%% 2 " 2 ((! $ n f ni ' N = N 0 e "!t!=.693 t / 2 c = m/s 0-7 T m/a γ0 = C2 / (N m2 ) 0 =4 nair =.000 nwater =.333 nglass =.520 ndiamond = 2.49 = 6.626! 0 # 34 J " s c = 240 ev nm ev = 602.! 0 "9 J Ci = Bq melectron = kg = u =.5 Mev/c2 mproton = u mneutron = u ev = J u = kg = 93.5 MeV/c2

3 Exam 4.00 SCORE: / 50 COMPREHENSIVE EXAM 7 May 2003 NAME: General Pysics II (PHSX 2020) Adam Jonston SEAT Number: Multiple coice: Eac question is wort 5 points.. Tis exam is for a course in. A. Music appreciation. B. Alcemy. C. Cosmetology. D. Feline anatomy. E. Pysics. F. I never knew nor cared. I just sowed up at 8:00 AM everyday for te dougnuts. 2. Te universe is currently expanding. Weter or not it will continue to expand is most directly determined by te universe s A. net carge. B. total mass. C. production of visible ligt. D. total number of neutrinos. E. average temperature. F. color. 3. Te wavelengt of a bowling ball rolling down a bowling alley is A. very very very small compared to most pysical quantities. B. very very very big compared to most pysical quantities. C. about te same pysical size as te bowling ball itself. D. about te same as te widt of te bowling alley. E. non-sensical. (Tere is no suc ting as a wavelengt for pysical objects.) F A poton as zero rest mass. Terefore it is allowed to A. travel at te speed of ligt. B. travel faster tan te speed of ligt. C. travel infinite distances. D. bot A & B. E. bot A & C. F. all A B & C. 5. In a fission reaction te total mass of te products must be A. te same as te original materials. B. greater tan te original materials. C. less tan te original materials. D. none of tese E. Tere is no way to predict tis. F If polarized ligt goes troug a polarizer to wat percentage of te original intensity will te polarized ligt s intensity be? A. 0 % B. 0% C. 50% D. 90% E. 00% F. It depends on te orientation of te polarizer.

4 7. Adam is riding is bicycle traveling past you at a constant speed measuring c. Wen e stops is bike e says tat e was riding for exactly one our. How long do you say tat e was riding is bike? A. Exactly one our. B. Less tan one our. C. More tan one our. D. Zero time. E. More information is needed to know te answer. F Tree ligt bulbs of te same resistance are connected in series to a single battery as sown. Wic of te tree will be te brigtest? A. Ligt bulb A. B. Ligt bulb B. C. Ligt bulb C. D. All tree will be exactly te same brigtness. 9. You pus a magnet into a complete loop of wire. As a result te wire exerts a force on te magnet tat is A. backward pusing away from te wire. D. rigt; perpendicular to te motion of te magnet. B. forward pulling towards te wire. E. More information is needed; specifically te orientation of te magnet. E. More information is needed to answer tis question. C. left; perpendicular to te motion of te magnet. F. None of tese. 0. Te Bor atom is a model of an atom wic sows A. ow multiple electrons must obey te Pauli exclusion principle. B. ow electrons beaving as waves exibit quantized energy states. C. ow nuclear reactions lose mass and convert tis to energy. D. A B & C are all correct. E. None of tese.. A neutral conducting spere is placed witin an electric field. Inside te conducting spere te electric field is A. greater in magnitude tan te field outside te spere. B. zero. C. less in magnitude tan te field outside te spere (but not zero). D. unable to be determined from te information given. 2. Imagine tat you are basking in te sun next to cool clear lake celebrating your summer vacation and aving a muc deserved and relaxing break. You look down into te water of te lake and see a fis. If you can see te fis ten you know tat A. te fis can see you. B. te fis cannot see you. C. te fis may or may not be able to see you it depends on some oter factor. D. you re not sure weter or not tat wretced fis can see you but you re bitter tat you re wasting a perfectly good relaxing moment of your summer vacation tinking about pysics. E. 42 E. soon you will wake up from your little dream and you ll realize tat you re really living a nigtmare: Taking a PHSX 2020 final exam.

5 NAME: Situation I: Te life of an electron A. [0 pts.] Imagine tat you sine some ligt on an unknown metal and electrons are detected coming off te metal. If te electrons ave a debroglie wavelengt of.50 nm wen you sine ligt of 650 nm on tis metal wat is te binding energy of te metal? B. [0 pts.] Te electrons emitted in te previous problem (wit a debroglie wavelengt of.50 nm) must be stopped! In order to do tis you ave two parallel plates wit a constant electric field between tem measuring V/m. Wat is te minimum distance required to bring tese electrons to rest in between tese parallel plates? C. Te parallel plates tat you use in te previous problem are given teir own carge by connecting tem as a capacitor to a circuit tat is sown below.. [5 pts.] If te carge on te capacitor is initially zero sow on te voltage versus time grap ow te voltage across tis capacitor would cange once te switc as been connect to allow current to flow in te circuit. 2. [5 pts.] Sow on te circuit diagram were/ow you would connect a voltmeter to measure te voltage describe in your grap.

6 Situation II: Te life of a poton A. [0 pts.] Remember tat ligt from Situation I wit a wavelengt of 650 nm? In order to obtain tis particular wavelengt you used a diffraction grating. How many lines (i.e. te scratces imbedded on tis grating) per centimeter are on tis particular diffraction grating if te first order of tis 650 nm wavelengt is viewed at an angle of 25.0 from te normal? B. [0 pts.] Remember tat fis tat you were looking at in multiple coice question #2? You are sining your red laser pointer so tat te red ligt (wit a wavelengt of 650 nm... ey wat a coincidence!) its te fis. From te fis s perspective te laser beam is coming down troug te water at an angle of 60.0 below te surface of te water. At wat angle (as measured from te normal perpendicular to te surface of te water) does your laser beam point in air? C. [0 pts.] You turn around and come face-to-face wit...yourself! You (a very andsome individual standing at.50 m tall) are looking at you in a converging mirror tat is 2.00 m away. Your image is rigt-side-up and appears to be twice as tall as you are in reality. Wat is te focal lengt of tis mirror?

7 Situation III: Te life of an alpa particle A. [0 pts.] A Plutonium nucleus ( Pu A = 239 Z = 94) alpa decays into Uranium. Write te equation for tis reaction including all of te above-mentioned nuclei and any oter products and teir values for A (total number of nucleons) and Z (total carge). B. [0 pts.] Calculate te energy released from above reaction. Some atomic masses tat migt be useful to you are listed. Helium-4 Plutonium-239 Uranium-235 Uranium-238 Hydrogen u u u u u C. [0 pts.] Let s say your alpa particle (Z = 2) wit a mass of kg is traveling troug a magnetic field. If te velocity of tis alpa particle is m/s wat is te minimum magnetic field required for tis alpa particle to navigate a circular pat wose radius is m? (Round your answer to 3 significant figures for full credit.)

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