AP Physics B 2009 Free-Response Questions Form B

Transcription

1 AP Phyc B 009 Free-Repone Queton Form B The College Board The College Board a not-for-proft memberhp aocaton whoe mon to connect tudent to college ucce and opportunty. Founded n 900, the aocaton compoed of more than 5,600 chool, college, unverte and other educatonal organzaton. Each year, the College Board erve even mllon tudent and ther parent, 3,000 hgh chool and 3,800 college through major program and ervce n college readne, college admon, gudance, aement, fnancal ad, enrollment, and teachng and learnng. Among t bet-known program are the SAT, the PSAT/NMSQT and the Advanced Placement Program (AP ). The College Board commtted to the prncple of excellence and equty, and that commtment emboded n all of t program, ervce, actvte and concern. 009 The College Board. All rght reerved. College Board, Advanced Placement Program, AP, AP Central, SAT, and the acorn logo are regtered trademark of the College Board. PSAT/NMSQT a regtered trademark of the College Board and Natonal Mert Scholarhp Corporaton. Permon to ue copyrghted College Board materal may be requeted onlne at: AP Central the offcal onlne home for the AP Program: apcentral.collegeboard.com.

2 Proton ma, Neutron ma, m p m n TABLE OF INFORMATION FOR 008 and 009 CONSTANTS AND CONVERSION FACTORS kg Electron charge magntude, -7-9 e.60 0 C.67 0 kg -9 electron volt, ev.60 0 J -3 8 Electron ma, m e 9. 0 kg Speed of lght, c m 3 - Unveral gravtatonal - 3 Avogadro number, N mol contant, G m kg Unveral ga contant, R 8.3 J (mol K) Acceleraton due to gravty at Earth urface, g 9.8 m -3 Boltzmann contant,.38 0 J K k B -7 unfed atomc ma unt, u.66 0 kg 93 MeV c Planck contant, h J ev Vacuum permttvty, Coulomb law contant, Vacuum permeablty, Magnetc contant, -5 3 hc.99 0 J m.4 0 ev nm C Nm 0 9 k 4p Nm C -7 m0 4p 0 (T m) A 7 0 k m 4 p - 0 (T m) A 5 5 atmophere preure, atm.0 0 N m.0 0 Pa UNIT SYMBOLS meter, m mole, mol watt, W farad, F klogram, kg hertz, Hz coulomb, C tela, T econd, newton, N volt, V degree Celu, C ampere, A pacal, Pa ohm, W electron-volt, ev kelvn, K joule, J henry, H PREFIXES VALUES OF TRIGONOMETRIC FUNCTIONS FOR COMMON ANGLES Factor Prefx Symbol q gga G nq mega M coq klo k tanq cent c mll m mcro m nano n 0 - pco p The followng conventon are ued n th exam. I. Unle otherwe tated, the frame of reference of any problem aumed to be nertal. II. The drecton of any electrc current the drecton of flow of potve charge (conventonal current). III. For any olated electrc charge, the electrc potental defned a zero at an nfnte dtance from the charge. IV. For mechanc and thermodynamc equaton, W repreent the work done on a ytem. --

3 ADVANCED PLACEMENT PHYSICS B EQUATIONS FOR 008 and 009 u u 0 + at x x0 + u0t + at u NEWTONIAN MECHANICS ( x ) u0 + a x - 0  F F ma Ffrc a c net mn u r t rf n q p mv J FDt Dp K mu g D U mgh W FDr co q P avg W Dt P Fucoq F U T -k x kx p T p p T F U G G f m k g Gm m - r Gm m - r a acceleraton F force f frequency h heght J mpule K knetc energy k prng contant length m ma N normal force P power p momentum r radu or dtance T perod t tme U potental energy u velocty or peed W work done on a ytem x poton m coeffcent of frcton q angle t torque ELECTRICITY AND MAGNETISM qq A area F 4p 0 r B magnetc feld E F C capactance d dtance q E electrc feld qq e emf UE qv 4p 0 r F force I current V Eavg - length d P power q Q charge V 4p  0 r q pont charge R retance Q C r dtance V t tme 0 C A U potental (tored) energy d V electrc potental or potental dfference Uc QV CV u velocty or peed r retvty DQ Iavg q angle Dt r R f m magnetc flux A V P Cp IR IV  C  C C R  R  R R p FB qubnq F BI nq B B m0 I p r fm BA co q Df eavg - Dt e B u m -3-

4 ADVANCED PLACEMENT PHYSICS B EQUATIONS FOR 008 and 009 FLUID MECHANICS AND THERMAL PHYSICS P P + rgh Fbuoy Au 0 rvg A u P + rgy + ru D a H P 0 DT ka DT L F A PV nrt NkBT K u W avg rm 3 kbt cont. 3k T m 3RT B M - PDV D U Q + W e e c W Q T H H - T H T C ATOMIC AND NUCLEAR PHYSICS E hf pc Kmax hf - f l h p DE ( Dmc ) A area e effcency F force h depth H rate of heat tranfer k thermal conductvty K avg average molecular knetc energy length L thckne M molar ma n number of mole N number of molecule P preure Q heat tranferred to a ytem T temperature U nternal energy V volume u velocty or peed u rm root-mean-quare velocty W work done on a ytem y heght a coeffcent of lnear expanon m ma of molecule r denty E energy f frequency K knetc energy m ma p momentum l wavelength f work functon WAVES AND OPTICS u f l n n c u n q n n q n nq c n + 0 f h M - h f dn R x m 0 0 q ml mll d d eparaton f frequency or focal length h heght L dtance M magnfcaton m an nteger n ndex of refracton R radu of curvature dtance u peed x poton l wavelength q angle GEOMETRY AND TRIGONOMETRY Rectangle A bh Trangle A bh Crcle A pr C pr Parallelepped V wh Cylnder V pr S pr + pr Sphere 4 3 V pr 3 S 4pr Rght Trangle a + b c a nq c b coq c a tanq b A area C crcumference V volume S urface area b bae h heght length w wdth r radu q c b 90 a -4-

5 009 AP PHYSICS B FREE-RESPONSE QUESTIONS (Form B) PHYSICS B SECTION II Tme 90 mnute 6 Queton Drecton: Anwer all x queton, whch are weghted accordng to the pont ndcated. The uggeted tme are about 7 mnute for anwerng each of Queton -4 and about mnute for anwerng each of Queton 5-6. The part wthn a queton may not have equal weght. Show all your work n th booklet n the pace provded after each part, NOT n the lavender nert.. (5 pont) An experment performed ung the apparatu above. A mall dk of ma m on a frctonle table attached to one end of a trng. The trng pae through a hole n the table and an attached narrow, vertcal platc tube. An object of ma m hung at the other end of the trng. A tudent holdng the tube make the dk rotate n a crcle of contant radu r, whle another tudent meaure the perod P. mr (a) Derve the equaton P p that relate P and m. mg 009 The College Board. All rght reerved. -5-

6 009 AP PHYSICS B FREE-RESPONSE QUESTIONS (Form B) The procedure repeated, and the perod P determned for four dfferent value of m, where m 0.0 kg and r 0.80 m. The data, whch are preented below, can be ued to compute an expermental value for g. m (kg) P () (b) What quantte hould be graphed to yeld a traght lne wth a lope that could be ued to determne g? (c) On the grd below, plot the quantte determned n part (b), label the axe, and draw the bet-ft lne to the data. You may ue the blank row above to record any value you may need to calculate. (d) Ue your graph to calculate the expermental value of g. 009 The College Board. All rght reerved. -6-

7 009 AP PHYSICS B FREE-RESPONSE QUESTIONS (Form B). (5 pont) Three partcle are arranged on coordnate axe a hown above. Partcle A ha charge q nc, and ntally on the y-ax at y m. The other two partcle each have charge q B nc and are held fxed on the x-ax at x m and x m, repectvely. (a) Calculate the magntude of the net electrc force on partcle A when t at y m, and tate t drecton. (b) Partcle A then releaed from ret. Qualtatvely decrbe t moton over a long tme. In another experment, partcle A of charge q nc njected nto a unform magnetc feld of trength 0.50 T drected nto the page, a hown below, enterng the feld wth peed 6000 m. A A (c) On the dagram above, ketch a complete path of partcle A a t move n the magnetc feld. (d) Calculate the magntude of the force the magnetc feld exert on partcle A a t enter the magnetc feld. (e) An electrc feld can be appled to keep partcle A movng n a traght lne through the magnetc feld. Calculate the magntude of th electrc feld and tate t drecton. 009 The College Board. All rght reerved. -7-

8 009 AP PHYSICS B FREE-RESPONSE QUESTIONS (Form B) 3. (5 pont) 3 An underground ppe carre water of denty 000 kg m to a fountan at ground level, a hown above. At -4 pont A, 0.50 m below ground level, the ppe ha a cro-ectonal area of.0 0 m. At ground level, the -4 ppe ha a cro-ectonal area of m. The water leave the ppe at pont B at a peed of 8. m/. (a) Calculate the peed of the water n the ppe at pont A. (b) Calculate the abolute water preure n the ppe at pont A. (c) Calculate the maxmum heght above the ground that the water reache upon leavng the ppe vertcally at ground level, aumng ar retance neglgble. (d) Calculate the horzontal dtance from the ppe that reached by water extng the ppe at 60 from the level ground, aumng ar retance neglgble. 009 The College Board. All rght reerved. -8-

9 009 AP PHYSICS B FREE-RESPONSE QUESTIONS (Form B) 4. (5 pont) The cylnder hown above ha an open top, and ga held nde t by a pton of ma m and area A. The ga nulated from t urroundng and ntally n equlbrum at volume V. Expre all algebrac anwer n term of the gven quantte and fundamental contant. (a) Determne the abolute preure P of the ga at equlbrum. The ga heated by a crcut that contan three retor, each of known retance R 0, connected n parallel to a power ource of emf e. The pton held fxed o that the ga reman at contant volume whle beng heated for a perod of tme t. (b) Determne the retance of the crcut. (c) Calculate the change n nternal energy of the ga. After the tme t, the crcut dconnected. The pton then releaed and the ga allowed to expand adabatcally untl t reache volume V. f (d) Indcate below whether the temperature ncreae, decreae, or reman the ame durng th proce. Increae Decreae Reman the ame Jutfy your anwer. (e) The ga then compreed othermally to t orgnal preure and volume. On the axe below, draw a PV dagram for the complete cycle decrbed n th queton, labelng V and V on the volume ax. f 009 The College Board. All rght reerved. -9-

10 009 AP PHYSICS B FREE-RESPONSE QUESTIONS (Form B) 5. (0 pont) A wde beam of whte lght ncdent normal to the urface of a unform ol flm. An oberver lookng down at -7 the flm ee green lght that ha maxmum ntenty at a wavelength of 5. 0 m. The ndex of refracton of the ol.7. (a) Calculate the peed at whch the lght travel wthn the flm. (b) Calculate the wavelength of the green lght wthn the flm. (c) Calculate the mnmum poble thckne of the flm. (d) The ol flm now ret on a thck lab of gla wth ndex of refracton.4, a hown n the fgure below. A lght ray ncdent on the flm at the angle hown. On the fgure, ketch the path of the refracted lght ray that pae through the flm and the gla lab and ext nto the ar. Clearly how any bendng of the ray at each nterface. You are NOT expected to calculate the ze of any angle. 009 The College Board. All rght reerved. -0-

11 009 AP PHYSICS B FREE-RESPONSE QUESTIONS (Form B) 6. (0 pont) The electron energy level above are for an electron confned to a certan very mall one-dmenonal regon of pace. The energy E n of the level, where n,, 3,..., gven by E n ne. Expre all algebrac anwer n term of E and fundamental contant. (a) On the dagram above, label the three excted energy level wth the value for ther energe n term of E, the energy of the ground tate. (b) Calculate the mallet frequency of lght that can be aborbed by an electron n th ytem when t n the ground tate, n. (c) If an electron raed nto the econd excted tate, draw on the dagram all the poble tranton that the electron can make n returnng to the ground tate. (d) Calculate the wavelength of the hghet energy photon that can be emtted n the tranton n part (c). END OF EXAM 009 The College Board. All rght reerved. --