Section I GO ON TO THE NEXT PAGE. PHYSICS C. Physics C has two exams: Physics C (Mechanics) and Physics C (Electricity & Magnetism):

Transcription

1 Prctice Test

2 PHYSICS C Physics C hs two exms: Physics C (Mechnics) n Physics C (Electricity & Mgnetism): Physics C (Mechnics) Physics C (Electricity & Mgnetism) First min. Sec. I, Multiple Choice Sec. I, Multiple Choice questions questions Secon min. Sec. II, Free esponse Sec. II, Free esponse questions questions You my tke just Mechnics or just Electricity n Mgnetism, or both. If you tke both, you will receive seprte gre for ech. Ech section of ech exmintion is percent of the totl gre; ech question in section hs equl weight. Clcultors re permitte on both sections of the exm. However, clcultors cnnot be shre with other stuents n clcultors with typewriterstyle (QWETY) keybors will not be permitte. On the following pges you will fin the Tble of Informtion tht is provie to you uring the exm. If you re tking Mechnics only, plese be creful to nswer numbers ; Electricity n Mgnetism only, plese be creful to nswer numbers 7; the entire exmintion (Mechnics n Electricity n Mgnetism), nswer numbers 7 on your nswer sheet. GO ON TO THE NEXT PGE. Crcking the P Physics C Exm

3 DVNCED PCEMENT PHYSICS C TE OF INFOMTION Proton mss, Neutron mss, Electron mss, vogro s number, Universl gs constnt, oltzmnn s constnt, CONSTNTS ND CONVESION FCTOS m p =.7 7 kg m n =.7 7 kg m e = 9. kg N =. mol =. J/(mol K) k =. J/K unifie tomic mss unit, Plnck s constnt, Vcuum permittivity, Coulomb s lw constnt, Vcuum permebility, Mgnetic constnt, tmosphere pressure, Electron chrge mgnitue, electron volt, Spee of light, Universl grvittionl constnt, ccelertion ue to grvity t Erth s surfce, u =. 7 kg = 9 mev/c h =. J s =. ev s hc =.99 J m =. ev nm e =. C /(N m ) k = /(pe ) = 9. 9 (N m )/C m = p 7 (T m)/ k9 = m /(p) = 7 (T m)/ tm =. N/m =. P e =. 9 C ev =. 9 J c =. m/s G =.7 (N m )/kg g = 9. m/s UNIT SYMOS meter, m mole, mol wtt, W fr, F kilogrm, kg hertz, Hz coulomb, C tesl, T secon, s newton, N volt, V egree Celsius, C mpere, pscl, P ohm, W electron volt, ev kelvin, K joule, J henry, H VUES OF TIGONOMETIC FUNCTIONS FO COMMON NGES q 7 9 sinq / / / / / cosq / / / / / tnq / / / PEFIXES Fctor Prefix Symbol 9 gig G meg M kilo k centi c milli m micro m 9 nno n pico p The following ssumptions re use in this exm. I. The frme of reference of ny problem is inertil unless otherwise stte. II. The irection of current is the irection in which positive chrges woul rift. III. The electric potentil is zero t n infinite istnce from n isolte point chrge. IV. ll btteries n meters re iel unless otherwise stte. V. Ege effects for the electric fiel of prllel plte cpcitor re negligible unless otherwise stte. GO ON TO THE NEXT PGE. Prctice Test

4 MECHNICS v x = v x + x t = ccelertion E = energy x = x + v x t + x t F = force f = frequency vx = vx + x( x x) h = height I = rottionl inerti ΣF F net = = J = impulse m m K = kinetic energy k = spring constnt p l = length F = t = ngulr momentum m = mss J = Ft = p P = power p = momentum p = mv r = rius or istnce T = perio Ff µ F t = time N DE = W = Fr U = potentil energy v = velocity or spee W = work one on system x = position K = m = coefficient of friction mv q = ngle P = E t = torque t ω = ngulr spee = ngulr ccelertion P = F v f = phse ngle DU g = mgdh v = c r r = ω τ = r F α = Στ = τ net I I I = r m = Σmr x cm mx i i = Σ Σm v = rω = r p = Iω K = Iω ω = ω + t q = q + ω t + t i F = S k x U S = k(dx) x = x mx cos(ωt + f) π T = = ω f T = π S T = π P F U m k l g Gm m r G = Gm m r G = EECTICITY ND MGNETISM qq F = = re E = mgnetic fiel πε r C = cpcitnce E F = istnce E = E = electric fiel q e = emf E = Q F = force I = current ε V E = x x V = E r V qi = πε r U = qq E qv = πε r V Q = C C = κε Cp = Ci = C C s I = i i Q t i i i U C = QDV = C(DV) = ρl E = ρj I = Nev V I = s = i = p P = IDV i i i J = current ensity = inuctnce l = length n = number of loops of wire per unit length N = number of chrge crriers per unit volume P = power Q = chrge q = point chrge = resistnce r = rius or istnce t = time U = potentil or store energy V = electric potentil v = velocity or spee r = resistivity F = flux k = ielectric constnt F = M qv l = µ I I r = µ l π r F = Il S = m ni Φ = ε = E l = Φ t ε = I t U = I GO ON TO THE NEXT PGE. Crcking the P Physics C Exm

5 ectngle = bh Tringle = bh Circle = pr C = pr s = rq GEOMETY ND TIGONOMETY = re C = circumference V = volume S = surfce re b = bse h = height l = length w = with r = rius s = rc length q = ngle CCUUS f f u = x u x x x n ( ) = nx x e x ( ) = e n x (ln x) = x x [sin( x)] = cos( x) x ectngulr Soli V = lwh [cos( x)] = sin( x) x Cyliner V = pr l S = prl + pr x r θ n x x = x n + e x x = e x n+, n Sphere x = ln x + x + V = pr S = pr cos( x) x = sin( x) ight Tringle + b + c sin( x) x = cos( x) sinq = c cosq = b c θ c b 9 VECTO PODUCTS = cosθ = sinθ tnq = b GO ON TO THE NEXT PGE. Prctice Test

6 PHYSICS C SECTION I, MECHNICS Time minutes Questions Directions: Ech of the questions or incomplete sttements below is followe by five suggeste nswers or completions. Select the one tht is best in ech cse n then mrk it on your nswer sheet.. rock is roppe off cliff n flls the first hlf of the istnce to the groun in t secons. If it flls the secon hlf of the istnce in t secons, wht is the vlue of t /t? (Ignore ir resistnce.) () () (C) / ( ) (D) ( ) (E). bubble strting t the bottom of so bottle experiences constnt ccelertion,, s it rises to the top of the bottle in some time, t. How much frther oes it trvel in the lst secon of its journey thn in the first secon? ssume tht the journey tkes longer thn secons. () (t + ) () (t ) (C) t (D) (t + ) (E) (t ). n object initilly t rest experiences time-vrying ccelertion given by = ( m/s )t for t. How fr oes the object trvel in the first secons? () 9 m () m (C) m (D) m (E) 7 m. Which of the following conitions will ensure tht ngulr momentum is conserve? I. Conservtion of liner momentum II. Zero net externl force III. Zero net externl torque () I n II only () I n III only (C) II n III only (D) II only (E) III only m θ F T. In the figure shown, tension force F T cuses prticle of mss m to move with constnt ngulr spee ω in circulr pth (perpeniculr to the pge) of rius. Which of the following expressions gives the mgnitue of F T? () mω () m ω g (C) m ω + g (D) m( ω g) (E) m ω + g ( ). n object (mss = m) bove the surfce of the Moon (mss = M) is roppe from n ltitue h equl to the Moon s rius (). With wht spee will the object strike the lunr surfce? () GM / () GM /( ) (C) GM / (D) GMm/ (E) GMm/( ) GO ON TO THE NEXT PGE. Crcking the P Physics C Exm

7 7. Preten tht someone mnge to ig hole stright through the center of the Erth ll the wy to the other sie. If n object were roppe own tht hole, which of the following woul best escribe its motion? ssume iel conitions n tht the object cnnot be estroye. () It woul fll to the center of the Erth n stop there. () It woul fll through the hole to the other sie, continue pst the opposite sie s opening, n fly into spce. (C) It woul oscillte bck n forth from one opening to the other inefinitely. (D) It woul oscillte bck n forth, but the mplitue woul ecrese ech time, eventully settling t the center of the Erth. (E) It woul fll to the other sie n stop there. 9. uniform cyliner, initilly t rest on frictionless, horizontl surfce, is pulle by constnt force F from time t = to time t = T. From time t = T on, this force is remove. Which of the following grphs best illustrtes the spee, v, of the cyliner s center of mss from t = to t = T? () v F time mss = m () v. uniform cyliner of mss m n rius r unrolls without slipping from two strings tie to verticl support. If the rottionl inerti of the cyliner is mr, fin the ccelertion of its center of mss. (C) time () g () g (C) g v time (D) g (D) (E) g v time (E) v time GO ON TO THE NEXT PGE. Prctice Test

8 . spce shuttle is lunche from Erth. s it trvels up, it moves t constnt velocity of m/s stright up. If its engines provie. W of power, wht is the shuttle s mss? You my ssume tht the shuttle s mss n the ccelertion ue to grvity re constnt. ().7 kg (). kg (C).7 kg (D). kg (E). kg. rubber bll (mss =. kg) is roppe from height of. m n, fter bouncing off the floor, rises lmost to its originl height. If the impct time with the floor is mesure to be. s, wht verge force i the floor exert on the bll? (). N () N (C) N (D) N (E) N. stellite is in circulr orbit roun Erth. If the work require to lift the stellite to its orbit height is equl to the stellite s kinetic energy while in this orbit, how high bove the surfce of Erth (rius = ) is the stellite? () () (C) (D) (E). isk of rius. m initilly t rest unergoes n ngulr ccelertion of. r/s. If the isk only rottes, fin the totl istnce trvele by point on the rim of the isk in. s. (). m (). m (C). m (D). m (E). m M M Support Support x surfce. The figure bove shows uniform br of mss M resting on two supports. block of mss M is plce on the br twice s fr from Support s from Support. If F n F enote the ownwr forces on Support n Support, respectively, wht is the vlue of F /F? () () (C). In the figure bove, smll bll slies own frictionless qurter-circulr slie of rius. If the bll strts from rest t height equl to bove horizontl surfce, fin its horizontl isplcement, x, t the moment it strikes the surfce. () () (C) (D) 7 (E) (D) (E) GO ON TO THE NEXT PGE. Crcking the P Physics C Exm

9 Screen y Screen prticle. The figure bove shows prticle executing uniform circulr motion in circle of rius. ight sources (not shown) cuse shows of the prticle to be projecte onto two mutully perpeniculr screens. The positive irections for x n y long the screens re enote by the rrows. When the show on Screen is t position x = (.) n moving in the +x irection, wht is true bout the position n velocity of the show on Screen t tht sme instnt? () y = (.); velocity in y irection () y = (.); velocity in +y irection (C) y = (.); velocity in y irection (D) y = +(.); velocity in y irection (E) y = +(.); velocity in +y irection F m x. toy cr n toy truck collie. If the toy truck s mss is ouble the toy cr s mss, then, compre to the ccelertion of the truck, the ccelertion of the cr uring the collision will be () ouble the mgnitue n in the sme irection () ouble the mgnitue n in the opposite irection (C) hlf the mgnitue n in the sme irection (D) hlf the mgnitue n in the opposite irection (E) epenent on the type of collision 9. homogeneous br is lying on flt tble. esies the grvittionl n norml forces (which cncel), the br is cte upon by exctly two other externl forces, F n F, which re prllel to the surfce of the tble. If the net force on the ro is zero, which one of the following is lso true? () The net torque on the br must lso be zero. () The br cnnot ccelerte trnsltionlly or rottionlly. (C) The br cn ccelerte trnsltionlly if F n F re not pplie t the sme point. (D) The net torque will be zero if F n F re pplie t the sme point. (E) None of the bove. n stronut lns on plnet whose mss n rius re ech twice tht of Erth. If the stronut weighs N on Erth, how much will he weigh on this plnet? () N () N (C) N (D), N (E), N m 7. The figure shows view from bove of two objects ttche to the en of rigi mssless ro t rest on frictionless tble. When force F is pplie s shown, the resulting rottionl ccelertion of the ro bout its center of mss is kf/(m). Wht is k? () () (C) (D) (E) GO ON TO THE NEXT PGE. Prctice Test 7

10 F (N) x (in m). If C, M,, n T represent the imensions of chrge, mss, length, n time respectively, wht re the imensions of the permittivity of free spce (e )? () T C /(M ) () T C /(M ) (C) M /(T C ) (D) C M/(T ) (E) T /(C M). prticle of mss m =. kg is cte upon by vrible force, F(x), whose strength is given by the grph given bove. If the prticle s spee ws zero t x =, wht is its spee t x = m? (). m/s ().7 m/s (C) m/s (D) m/s (E) m/s y m x m v v. The rius of collpsing spinning str (ssume to be uniform sphere) ecreses to its initil vlue. Wht is the rtio of the finl rottionl kinetic energy to the initil rottionl kinetic energy? () () (C) (D) (E) v. The figure shown is view from bove of two cly blls moving towr ech other on frictionless surfce. They collie perfectly inelsticlly t the inicte point n re observe to then move in the irection inicte by the post-collision velocity vector, v9. If m = m wht is v? () v (sin )/( sin ) () v (cos )/( cos ) (C) v ( cos )/(cos ) (D) v ( sin )/(sin ) (E) v (cos )/( sin ) v' m m m. bll is projecte with n initil velocity of mgnitue v = m/s towr verticl wll s shown in the figure bove. How long oes the bll tke to rech the wll? (). s (). s (C). s (D). s (E). s GO ON TO THE NEXT PGE. Crcking the P Physics C Exm

11 s =. m M z ( m, m) ( m, m) Pth. In the figure bove, the coefficient of sttic friction between the two blocks is.. If the blocks oscillte with frequency of. Hz, wht is the mximum mplitue of the oscilltions if the smll block is not to slip on the lrge block? (). cm (). cm (C). cm (D) 7. cm (E) 9. cm 7. When two objects collie, the rtio of the reltive spee fter the collision to the reltive spee before the collision is clle the coefficient of restitution, e. If bll is roppe from height H onto sttionry floor, n the bll rebouns to height H, wht is the coefficient of restitution of the collision? () H H () H H (C) H H (D) H H (E) ( H H ) F cm cm. The figure bove shows squre metl plte of sie length cm n uniform ensity, lying flt on tble. force F of mgnitue N is pplie t one of the corners, s shown. Determine the torque prouce by F reltive to the center of rottion. () N m (). N m (C). N m (D). N m (E). N m (, ) Pth 9. smll block of mss m =. kg is pushe from the initil point (x i, z i ) = ( m, m) upwr to the finl point (x f, z f ) = ( m, m) long the pth inicte. Pth is portion of the prbol z = x, n Pth is qurter circle whose eqution is (x ) + (z ) =. How much work is one by grvity uring this isplcement? () J () J (C) 9 J (D) J (E) J spring constnt = k x = m x =. In the figure shown, the block (mss = m) is t rest t x =. s it moves bck towr the wll ue to the force exerte by the stretche spring, it is lso cte upon by frictionl force whose strength is given by the expression bx, where b is positive constnt. Wht is the block s spee when it first psses through the equilibrium position (x = )? () ( k+ b) m () ( k b) m ( + ) ( ) (C) k b m (D) k b m (E) k b m ( ) x GO ON TO THE NEXT PGE. Prctice Test 9

12 x = x x =. The ro shown bove cn pivot bout the point x = n rottes in plne perpeniculr to the pge. Its liner ensity, λ, increses with x such tht λ(x) = kx, where k is positive constnt. Determine the ro s moment of inerti in terms of its length,, n its totl mss, M. () M () M (C) M (D) M (E) M. prticle is subjecte to conservtive force whose potentil energy function is U(x) = (x ) x where U is given in joules when x is mesure in meters. Which of the following represents position of stble equilibrium?. t wht ngle to the horizontl shoul n iel projectile be lunche so tht its horizontl isplcement (the rnge) is equl to its mximum verticl isplcement? () sin (/g) () cos (/g) (C) (D) tn (E) tn. prticle s kinetic energy is chnging t rte of. J/s when its spee is. m/s. Wht is the mgnitue of the force on the prticle t this moment? (). N (). N (C). N (D) 9. N (E) N. n object of mss kg is cte upon by three externl forces, ech of mgnitue N. Which of the following coul NOT be the resulting ccelertion of the object? () m/s () m/s (C) m/s (D) m/s (E) m/s () x = () x = (C) x = (D) x = (E) x = STOP END OF SECTION I, MECHNICS Crcking the P Physics C Exm

13 I PHYSICS C SECTION II, MECHNICS Time minutes Questions Directions: nswer ll three questions. The suggeste time is bout minutes per question for nswering ech of the questions, which re worth points ech. The prts within question my not hve equl weight. Mech. mssless, frictionless pulley is suspene from rigi ro ttche to the roof of n elevtor cr. Two msses, m n M (with M > m), re suspene on either sie of the pulley by light, inextenble cor. The istnce from the top of the elevtor cr to the center of mss of the pulley, y p, is fixe. top of elevtor shft cble y p m M elevtor cr () ssume tht the elevtor cr is escening t constnt velocity. For ech of the following, write your nswer in terms of m, M, n g. (i) Determine the ccelertions of the msses. (ii) Fin the tension in the cor. (b) Now ssume tht the elevtor cr is escening with nonzero (but constnt) ccelertion, b. (i) Stte why the coorinte system tht uses the center of the pulley s its origin is not n inertil reference system. For prts (ii) n (iii), use the top of the elevtor shft s reference. Write your nswers in terms of m, M, g, n b. (ii) Fin the ccelertion of the msses. (iii) Determine the tension in the cor. (iv) For wht vlue of b woul the nswer to prt (iii) be zero? GO ON TO THE NEXT PGE. Prctice Test

14 I Mech. nrrow tunnel is rille through Erth (mss = M, rius = ), connecting points P n Q, s shown in the igrm on the left below. The perpeniculr istnce from Erth s center, C, to the tunnel is x. pckge (mss = m) is roppe from Point P into the tunnel; its istnce from P is enote y n its istnce from C is enote r. See the igrm here. P P C x C x y r pckge Q Q () ssuming tht Erth is homogeneous sphere, use the fct tht the grvittionl force F on the pckge is ue to m n the mss contine within the sphere of rius r < to show tht GMm F =- r (b) (c) Use the eqution F(r) = U/r to fin n expression for the chnge in grvittionl potentil energy of the pckge s it moves from Point P to point where its istnce from Erth s center is r. Write your nswer in terms of G, M, m,, n r. pply Conservtion of Energy to etermine the spee of the pckge in terms of G, M,, x, n y. (Ignore friction.) () (i) t wht point in the tunnel tht is, for wht vlue of y will the spee of the pckge be mximize? (ii) Wht is this mximum spee? (Write your nswer in terms of G, M,, n x.) GO ON TO THE NEXT PGE. Crcking the P Physics C Exm

15 I Mech. The igrm below is view from bove of three sticky hockey pucks on frictionless horizontl surfce. The pucks with msses m n m re connecte by mssless rigi ro of length n re initilly t rest. The puck of mss m is moving with velocity v irectly towr puck m. When puck m strikes puck m, the collision is perfectly inelstic. m m v m () (b) Immeitely fter the collision, (i) where is the center of mss of the system? (ii) wht is the spee of the center of mss? (Write your nswer in terms of v.) (iii) wht is the ngulr spee of the system? (Write your nswer in terms of v n.) Wht frction of the system s initil kinetic energy is lost s result of the collision? STOP END OF SECTION II, MECHNICS Prctice Test

16 PHYSICS C SECTION I, EECTICITY ND MGNETISM Time minutes Questions Directions: Ech of the questions or incomplete sttements below is followe by five suggeste nswers or completions. Select the one tht is best in ech cse n mrk it on your nswer sheet.. nonconucting sphere is given nonzero net electric chrge, +Q, n then brought close to neutrl conucting sphere of the sme rius. Which of the following will be true? () n electric fiel will be inuce within the conucting sphere. () The conucting sphere will evelop net electric chrge of Q. (C) The spheres will experience n electrosttic ttrction. (D) The spheres will experience n electrosttic repulsion. (E) The spheres will experience no electrosttic interction.. Ech of the following ionize isotopes is projecte with the sme spee into uniform mgnetic fiel such tht the isotope s initil velocity is perpeniculr to. Which combintion of mss n chrge woul result in circulr pth with the lrgest rius? () m = u, q = e () m = 7 u, q = e (C) m = u, q = e (D) m = 9 u, q = e (E) m = u, q = e 7. Which set of cpcitors, C n C, woul rech mximum chrge most rpily? () C = μf n C = μf, rrnge in prllel () C = μf n C = μf, rrnge in series (C) C = μf n C = μf, rrnge in prllel (D) C = μf n C = μf, rrnge in series (E) More thn one of the bove woul be most rpi. GO ON TO THE NEXT PGE. Crcking the P Physics C Exm

17 9. n ellipsoi-shpe conuctor is negtively chrge. Which one of the following igrms best illustrtes the chrge istribution n electric fiel lines? () C D () (C). The four wires shown bove re ech me of luminum. Which wire will hve the gretest resistnce? () Wire () Wire (C) Wire C (D) Wire D (E) ll the wires hve the sme resistnce becuse they re ll compose of the sme mteril.. Which of the following is NOT equl to one tesl? () J/( m ) () kg/(c s) (C) N/( m) (D) V s/m (E) N/V (D) (E). The figure bove shows two Gussin surfces: cube with sie length n sphere with imeter. The net electric chrge enclose within ech surfce is the sme, +Q. If Φ C enotes the totl electric flux through the cubicl surfce, n Φ S enotes the totl electric flux through the sphericl surfce, then which of the following is true? () Φ C = (π/)φ S () Φ C = (π/)φ S (C) Φ C = Φ S (D) Φ C = (/π)φ S (E) Φ C = (/π)φ S GO ON TO THE NEXT PGE. Prctice Test

18 neutrl insulting support Questions - Ech of the resistors shown in the circuit below hs resistnce of Ω. The emf of the iel bttery is V. q ε x. The figure bove shows two lrge verticl conucting pltes tht crry equl but opposite chrges. bll of mss m n chrge q is suspene from light string in the region between the pltes. If the voltge between the pltes is V, which of the following gives the ngle θ? () cos (qv/mgx) () sin (qv/mgx) (C) tn (qv/mgx) (D) cos (qv/x) (E) sin (qv/x). n object crries chrge of C. How mny excess electrons oes it contin? (). (). (C). 9 (D). 9 (E). 9. How much current is provie by the source? () m () m (C) m (D) 7 m (E) 9 m. Wht is the rtio of the power issipte by to the power issipte by? () /9 () / (C) (D) (E) 9 GO ON TO THE NEXT PGE. Crcking the P Physics C Exm

19 7. Wht is the vlue of the following prouct? µf Ω (). henry (). mpere per coulomb (C). weber (D). secon (E). volt per mpere y x m. copper wire in the shpe of circle of rius m, lying in the plne of the pge, is immerse in mgnetic fiel,, tht points into the plne of the pge. The strength of vries with time, t, ccoring to the eqution (t) = t( t) where is given in tesls when t is mesure in secons. Wht is the mgnitue of the inuce electric fiel in the wire t time t = s? () (/π) N/C () N/C (C) N/C (D) π N/C (E) π N/C 9. In the figure bove, the top hlf of rectngulr loop of wire, x meters by y meters, hngs verticlly in uniform mgnetic fiel,. Describe the mgnitue n irection of the current in the loop necessry for the mgnetic force to blnce the weight of the mss m supporte by the loop. () I = mg/x, clockwise () I = mg/x, counterclockwise (C) I = mg/ x+ y, clockwise (D) I = mg/ x+ y, counterclockwise (E) I = mg/(x+y), clockwise GO ON TO THE NEXT PGE. Prctice Test 7

20 +Q +q xis fixe in position. soli nonconucting cyliner of rius n length contins volume chrge ensity given by the eqution ρ(r) = (+ C/m )r, where r is the ril istnce from the cyliner s centrl xis. This mens tht the totl chrge contine within concentric cyliner of rius r < n length < is equl to πr. Fin n expression for the strength of the electric fiel insie this cyliner. () /e r () r/e. The figure bove shows two positively chrge prticles. The +Q chrge is fixe in position, n the +q chrge is brought close to +Q n relese from rest. Which of the following grphs best epicts the ccelertion of the +q chrge s function of its istnce r from +Q? () r (C) r/e (D) r /e () (E) r /e r I I (C) (D) r. The figure bove shows pir of long, stright currentcrrying wires n four mrke points. t which of these points is the net mgnetic fiel zero? () Point only () Points n only (C) Point only (D) Points n only (E) Point only (E) r r GO ON TO THE NEXT PGE. Crcking the P Physics C Exm

21 S Q = µc C = µf. n electric ipole consists of pir of equl but opposite point chrges of mgnitue. nc seprte by istnce of. cm. Wht is the electric fiel strength t the point miwy between the chrges? () () 9. V/m (C). V/m (D). V/m (E) 7. V/m Q = µc C = µf. Once the switch S in the figure bove is close n electrosttic equilibrium is regine, how much chrge will be store on the positive plte of the µf cpcitor? () 9 µc () µc (C) µc (D) 7 µc (E) µc X Y. metl br of length is pulle with velocity v through uniform mgnetic fiel,, s shown bove. Wht is the voltge prouce between the ens of the br? () v, with Point X t higher potentil thn Point Y () v, with Point Y t higher potentil thn Point X (C) v, with Point X t higher potentil thn Point Y (D) v, with Point Y t higher potentil thn Point X (E) None of the bove v insulting support. The figure bove shows cross section of two concentric sphericl metl shells of rii n, respectively. Fin the cpcitnce. () /(πε ) () /(πε ) (C) πε (D) πε (E) πε 7. Trveling t n initil spee of. m/s, proton enters region of constnt mgnetic fiel,, of mgnitue. T. If the proton s initil velocity vector mkes n ngle of with the irection of, compute the proton s spee s fter entering the mgnetic fiel. (). m/s () 7. m/s (C). m/s (D). m/s (E). m/s GO ON TO THE NEXT PGE. Prctice Test 9

22 Section I Questions - There is initilly no current through ny circuit element in the following igrm. ε r S. fter hving been close for long time, the switch is suenly opene. Wht is the current through r immeitely fter S is opene? () () (C) (D) ε r+ ε r+ ε( r+ ) r ε( ) (E) r( ) +. Wht is the current through r immeitely fter the switch S is close? () () ε r+ ε (C) r+ (D) ε( r+ ) r (E) ε( ) r + 9. fter the switch hs been kept close for long time, how much energy is store in the inuctor? () () (C) (D) (E) ε ( r+ ) ( r+ ) ( r+ ) ( ) ( r+ ) ( r+ ) ε ε ε ε X Y. soli, neutrl metl sphere of rius contins smll cvity, sphericl hole of rius s shown bove. Within this cvity is chrge, +q. If E n E Y enote the strength of the electric fiel t points X n Y, respectively, which of the following is true? () E Y = E X () E Y = E X (C) E Y = E X (D) E Y = (/)E X (E) E Y = (/) E X +q GO ON TO THE NEXT PGE. Crcking the P Physics C Exm

23 +Q +Q y(m) P x(m). Two prticles of chrge +Q re locte on the x-xis, s shown bove. Determine the work one by the electric fiel to move prticle of chrge Q from very fr wy to point P. () kq kq () (C) kq kq (D) (E) kq. Wht is the mximum number of W light bulbs tht coul be connecte in prllel with V source? The totl current cnnot excee or the circuit will blow fuse. () () (C) 9 (D) (E). The metl loop of wire shown bove is situte in mgnetic fiel pointing out of the plne of the pge. If ecreses uniformly in strength, the inuce electric current within the loop is () clockwise n ecresing () clockwise n incresing (C) counterclockwise n ecresing (D) counterclockwise n constnt (E) counterclockwise n incresing. bttery is connecte in series with switch, resistor of resistnce, n n inuctor of inuctnce. Initilly, there is no current in the circuit. Once the switch is close n the circuit is complete, how long will it tke for the current to rech 99% of its mximum vlue? 99 () (ln ) ε () ( r+ ) (C) (ln ) (D) (ln 99 ) (E) (ln ) GO ON TO THE NEXT PGE. Prctice Test

24 re = W vcuum ielectric slb vcuum I I S X. ielectric of thickness is plce between the pltes of prllel-plte cpcitor, s shown bove. If K is the ielectric constnt of the slb, wht is the cpcitnce? ε ( + K) () () (C) (D) (E) ε ( + K) ε ( K + ) Kε K + ( ) Ke +Q Q 7. Consier the two source chrges shown bove. t how mny points in the plne of the pge, in region roun these chrges re both the electric fiel n the electric potentil equl to zero? () () (C) (D) (E) I Z U I. The figure bove shows four current-crrying wires pssing perpeniculrly through the interior of squre whose vertices re W, X, Y, n Z. The points where the wires pierce the plne of the squre (nmely,, S, T, n U) themselves form the vertices of squre ech sie of which hs hlf the length of ech sie of WXYZ. If the currents re s lbele in the figure, wht is the bsolute vlue of where the integrl is tken roun WXYZ? () µ I () µ I (C) µ I (D) µ I (E) µ I T Y GO ON TO THE NEXT PGE. Crcking the P Physics C Exm

25 +Q cm Q +Q cm Pth q +Q Pth 7. Two point chrges, ech +Q, re fixe istnce prt. prticle of chrge q n mss m is plce s shown in the figure bove. Wht is this prticle s initil ccelertion when relese from rest? 9. prticle with chrge +q is move from point to point long pth in the picture bove. Its chnge in potentil energy is U. If chrge of q is then move from to long pth, its chnge in potentil energy will be () U () U () () (C) (C) U (D) U (D) (E) Cnnot be etermine without knowing the vlues of Q n Q (E) STOP END OF SECTION I, EECTICITY ND MGNETISM Prctice Test

26 I PHYSICS C SECTION II, EECTICITY ND MGNETISM Time minutes Questions Directions: nswer ll three questions. The suggeste time is bout minutes per question for nswering ech of the questions, which re worth points ech. The prts within question my not hve equl weight. E & M. uniformly chrge, nonconucting, circulr ring of rius crries chrge +Q. Its centrl xis is lbele the z-xis, n the center of the ring is z =. Points bove the ring on the z-xis hve positive z-coorintes; those below hve negtive z-coorintes. z-xis +Q, uniformly istribute roun the ring z = () Clculte the electric potentil t n rbitrry point on the z-xis. Write your nswer in terms of Q, z,, n funmentl constnts. (b) (i) t wht point(s) on the z-xis will the potentil hve its gretest vlue? (ii) Wht is this mximum potentil vlue? (c) () Fin n expression for the electric fiel (mgnitue n irection) t n rbitrry point on the z-xis. Write your nswer in terms of Q, z,, n funmentl constnts. positive chrge is relese from rest t z = + on the z-xis. Describe the subsequent motion of the positive chrge. Justify your nswer. GO ON TO THE NEXT PGE. Crcking the P Physics C Exm

27 I E & M. In the circuit shown below, the cpcitor is initilly unchrge n there is no current in ny circuit element. ε r S C In ech of the following, k is number greter thn ; write ech of your nswers in terms of e, r,, C, k, n funmentl constnts. () t t =, the switch S is move to position. (i) t wht time t is the current through equl to k of its initil vlue? (ii) t wht time t is the chrge on the cpcitor equl to k of its mximum vlue? (iii) t wht time t is the energy store in the cpcitor equl to k of its mximum vlue? (b) fter the switch hs been t position for very long time, it is then move to position. et this reefine t = for purposes of the following questions. (i) (ii) How long will it tke for the current through to equl of its initil vlue? k t wht time t is the chrge on the cpcitor equl to of its initil vlue? k GO ON TO THE NEXT PGE. Prctice Test

28 I E & M. The igrm below shows two prllel conucting rils connecte by thir ril of length, rise to n ngle of θ with the horizontl (supporte by pir of insulting columns). metl strip of length, mss m, n resistnce is free to slie without friction own the rils. The pprtus is immerse in verticl, uniform mgnetic fiel,. The resistnce of the sttionry rils my be neglecte. Y X θ θ () (b) (c) s the strip slies own the rils with instntneous spee v, etermine (i) the inuce emf. (Write your nswer in terms of,, v, n θ.) (ii) the irection of the inuce current in the strip (X to Y, or Y to X?). (iii) the vlue of the inuce current. (Write your nswer in terms of,,, v, n θ.) The strip XY will eventully slie own the rils t constnt velocity. Derive n expression for this velocity in terms of,,, m, g, n θ. When the strip is sliing with the constnt velocity etermine in prt (b), show tht the power issiption in the strip is equl to the rte t which grvity is oing work on the strip. STOP END OF EXM Crcking the P Physics C Exm

29 Completely rken bubbles with No. pencil. If you mke mistke, be sure to erse mrk completely. Erse ll stry mrks.. YOU NME: (Print) st First M.I.. YOU NME First letters of lst nme FIST INIT MID INIT SIGNTUE: DTE: HOME DDESS: (Print) Number n Street C C C C C C City Stte Zip Coe PHONE NO.: IMPOTNT: Plese fill in these boxes exctly s shown on the bck cover of your test book. D E F G H D E F G H D E F G H D E F G H D E F G H D E F G H. TEST FOM. TEST CODE. EGISTTION NUME I J I J I J I J I J I J. DTE OF ITH Month Dy Yer JN FE M P MY JUN JU UG SEP OCT NOV DEC C D E F G H I J K M N O P Q GENDE ME FEME K M N O P Q S T U V W X Y Z K M N O P Q S T U V W X Y Z K M N O P Q S T U V W X Y Z K M N O P Q S T U V W X Y Z K M N O P Q S T U V W X Y Z K M N O P Q S T U V W X Y Z