Focal Length of Mirror - Optics and Modern Physics - Solved Past Paper, Exams of Physics

Download Focal Length of Mirror - Optics and Modern Physics - Solved Past Paper and more Exams Physics in PDF only on Docsity! a 6. Physics 228- Final Exam May 8, 2007 Profs. Coleman and Zimmermann 9. Your name sticker | = : 10. with exam code a Ii. SIGNATURE: __ Turn off your cell phone now! The exam will last, from 4:00 p.m. to 7:00 pam. Use a #2 pen- cil to make entries on the answer sheet. Enter the following ID information now, before the exam starts. In the section labelled NAME (Last, First, M.1.) enter your last name, then fill in the empty circle for a blank, then enter your first name, another blank, and finally your middle initial. Under STUDENT # enter your 9-digit, Identification Number. Enter 228 under COURSE, and your section number (see label above) under SEC. Under CODE enter the exam code given above. During the exam, you may use pencils, a calculator, and one handwritten 8.5 x 11 inch sheet with formulas and notes, with- out attachments. There are 32 multiple-choice questions on the exam. For cach question, mark only one answer on the answer sheet. There is no deduction of points for an incorrect answer, so even if you cannot work out the answer to a question, you should make an educated guess. At the cnd of the exam, hand in the answer sheet and the cover page. Retain this question paper for future reference and study. When you are asked to open the exam, make sure that your copy contains all 32 questions. Rai our hand if this is not the case, and a proctor will help you. Also raise your hand during the exam if you have a question. Please SEGN the cover sheet under your name sticker. A proctor will check your name sticker and your student ID some- time during the exani. Please have them ready. Good luck. Possibly Useful Information Speed of light: ¢ = 3.00 x 10° m/s Angstrém: 1 A = 10779 m Electron. charge: g. = —e = ~1.602 x 107° G Elect. mass: m, = 0.00055 u = 9.11 x 107%! kg = 0.512 MeV/c? Proton mass: mp = 1.007276 u = 1.672622 x 107°” kg = 938.272 MeV/c? . Atomic mass unit: u = 1.660539 x 10°??-ke = 931.494 MeV/c? Boltzmann's constant: kg = 8.617 x 107% eV/K Rydberg constant = 13.6 eV Bohr magneton: pp = 9.274 x 10°74 J/T = 5.788 x 107° eV/T 69 = 8.85 x 107? C?/(Nm?) LeV = 1.602 x 10° J Planck’s constant/27: fi = 1.0545 x 10-S4Js = 6.583 x 107 eVs Planck’s constant: fh = 6.626 x 10°4Js = 4.136 x 1078 eVs 1. Which diagram below illustrates the path of a light ray as tt travels from a given point X in air to another given point Y in glass? |. —s 1S ' , Ten * ‘ Ael oq \ \ 6 i “Se lL x oa om nt 2. A concave mirror is to project an image onto a screen 48 cm away from the mirror such that the image is three times bigger than the object. What must be the focal length of the mirror? aL alos 4 S2t QBomn a) None of the other answers = 43/3- locm b) 0.083 cm 5 Si fF 5, = 4813 12cm ad 16cm L et at =) 4s I2em tc) e) 24cm s le 43 10. Le nh means c g Vo an also quested. W. There spo vay KH dakemine an “alpsolule velocity", became aewodton te ie prseple ab pyecial relotintny ' Ye ews of pps oye Ye same va alk meriol cohen e frames. 9. Photon A has twice the energy of photon B. What is the ratio of the momentum of photon A to that of Photon B. a} 1/4 b) 1/2 ce} ol 2 e) 4 10. In the Bohr model of the hydrogen atom, let the electron’s orbital angular momentum. be L, its orbital radius be r, and its speed be v. Pick the correct statement. a) Land r are quantized; v is not b) Land v are quantized; r is not ©) sand v are quantized; L is not @ L, r, and v are all quantized e) Lis quantized; r and v are not il. An observer is in a closed laboratory in the gravity-free environ- ment of outer space. She wishes to determine whether the labo- ratory is at rest or in motion at a constant. velocity. a) She can find out by performing the Michelson-Morley ex- periment. b) She can find out. b wall in various dir and after the bounce. None of the other answ d) She can find out by comparing two different clocks in the laboratory over a period of time. c) She can find out by measuring her mass. y bouncing a perfectly elastic ball off the tions and measuring the velocity before rs will work. 12. After 2 hours, # of the initial amount of a certain radioactive yed. The half-life of the isotope isotope has dec a) 15 min. 30 min. ¢} 45 min. a) 60 min. e) 2 hours 13. 14, 16, IB, The de Broglie wavelength of an electron whose kinetic energy is 54.0 eV is a) 2.50 nm b) 0.962 nm ¢) 23.0 nm 0.167 nm e) 0.333 nm A hydrogen atom is in the 3d state (n = 3, @ = 2}. How many distinct values of the z component of the electron’s total angular momentum are possible? (Include electron spin.} a) 1 b) 2 oc) 4 e) Jn a metal, at the absolute zero of temperature a) al] motion ccases b} the Fermi energy is zero ¢) the Fermi speed is zero d) the average kinetic energy of the conduction electrons is zero the average kinetic energy of the conduction electrons dif- fers significantly from zero 15. The reaction 7H + *H ~ *f1+1'H produces protons. The Q of the reaction is a) 3.27 MeV 6, b) 4.03 MeV c) 17.59 MeV d) 1.04 MeV e) 7.06 MeV The needed ma: u, 9H 3.016049 u, ' UL are hydrogen: 1.007825 un, deuterium: 2.014102 He 3.016029 u, *He 4.002603 u, neutron 1.008665 @ 6 \y - 8 Agnm Ez S¢ev « OSMW = con we relay ae Ev pea p= mE = = frmutor : hi. Getto Ze A.tetos See lorie” ;] Low ¥ won. = ONE Fam & voaluné- a 2 Epean +0. €) Q? ( Le 2or4or-3.0160% 007825) *O3L5 Me 6.006395 + 731.5 MV = 403M voles @ Py ’/ 3 7 i, Yalenen 8. LO. Grdudun holes in fue vorlence +t 4 bench corm Khe cornea my Ss Me tM J Teue (3.60 binding €) Man & Unptim, Yo Tene xe = S% (Brding ani } Betz te / True m(Yo) ne] <a 5o + Be, Became hnon 0 grride. d) ts Fave, Asin = 1.22% @- IA 2S wy se LIDAL aA L aA ge UG Hom ELLE SHUI 5G lol FL x ober 6x [On 25.6 a) AG Rd = 2x(2e41) a 17. Ina doped semiconductor material of the p-type a) the density of conduction electrons far exceeds the density of holes b) the holes carry negative charge c) the current uitied mainly by the electrons @D the current is carried mainly by the holes e) the valence band is full 18. Which of the following is not true? a) The rest mags of a hydrogen atom is less than the sum of the rest masses of an electron and a proton. b) The rest mass of a helium nucleus is Jess than the sum of the of two protons and 4 of an iron nul 38Fe) is less than the swm of the rest mass of 13 @ particles and 4 neutrons. d) The rest mass of a nrantum nucleus (285U) is less then the sum of the rest masses of 1}°Rn, }2?Cd, and 3 neutrons. @ neutrons. 19. What is the approximate distance between two bright point sources of light on Earth that astronauts can just resolve by eye when they are orbiting 250 km above the Barth? Assume a wavelength of 500 mm, and a pupil diameter of 6 mm. Assume index of refraction of the eye = 1.00. 25.4.m b) 40.6 m c) 0.025 m d) 135m e) 613m 20. Tlow many electrons can be accomodated in the 4f level of an atom? Ou a) 3 b) 4 c) 7 dj) 12 28. 30. al. The atomic number of carbon is 6, that of nilrogon 7. If a small fraction of carbon atoms in the crystal lattice of diamond (an insulator with a bandgap of 5.4 eV) are replaced by nitrogen atoms (“uitrogen-doping” of diamond), what kind of solid is formed? a) An intrinsic semiconductor An n-type semiconductor c) A ptype semiconductor d} A metal e) A superconductor ‘The following decay and reaction each involve a neutrino. Kia ptt? ?4+n—> ptt+e What are the identities of the mi secoud equations, respectively? ing ueutrmos in the first and a) By, Ve b) Uy, Be C) May Mp d) v,, Be A particle is a combination of a down quark (d) and an anti-up quark (i). The particle is a a) po b) a co) dy oat e) Ja Baryons differ from mesons in that. baryons: a) have two quarks. b) have integer spin. c) have half-integer baryon number. d) contain both quarks and antiquarks. ® have three quarks. No hes one nore, Gado Eee Co f Mea on Cede dongs 7 nm Spe SQru conducts. kc? —+ + Vy a) ~| +1 oO )} Py Bones — 99 97 a 32. The strong interaction is mediated by: @® gluons b) photons ¢) neutrinos a) quarks e) Z° particles