(B) F t=mv (C) v 2 =a x F (D) v = m t (E) all of the above

Transcription

1 Each exam usually consiss of 10 Muliple choice quesions which are concepual in naure. They are ofen based upon he assigned hough quesions from he homework. There are also 4 problems in each exam, based upon he assigned homework problems. Parial credi may be awarded for he problems. Physical consans and equaion shees are provided for he exam. Par I Muliple Choice (4 poins. ea.). Physics is (A) Naural Philosophy. (B) he science of maer and energy. (C) an experimenal science involving inerplay beween observaion and he developmen of heory. (D) all of he above.. Physics is (A) Unnaural Philosophy. (B) he science of heaer and synergy. (C) an experimenal science involving inerplay beween observaion and he developmen of heory. (D) all of he above.. In physics, an "Idealized Model" (A) is a mahemaical descripion of naure ha agrees wih observaion perfecly in all respecs. (B) is a mahemaical descripion of naure ha conains some simplifying assumpions and agrees wih observaions well enough when hose assumpions apply. (C) is a mahemaical descripion of naure ha is independen of any realiy. (D) recenly appeared in UPN's "America's Nex Top Model".. The following variables are commonly seen in equaions. The name of he quaniy represened by each variable, and is dimension(s), are also shown. x disance (L) (T) m mass (M) a acceleraion (L/T 2 ) v speed (L/T) F force (ML/T 2 ) Using he informaion above, which of he following equaions ha is dimensionally correc (ha is, he dimensions of quaniies wihin he equaions are consisen). (A) F =m x 2 (B) F =mv (C) v 2 =a x F (D) v = m (E) all of he above 1

2 . When dealing wih he inrinsic errors in measuremen, (A) random errors will average ou over several measuremens, bu sysemaic errors will remain consan. (B) random errors will accumulae over several measuremens, bu sysemaic errors will average ou. (C) boh random and sysemaic errors will remain consan over several measuremens. (D) boh random and sysemaic errors will accumulae over several measuremens.. If we were o muliply by.073 he resul should have (A) 2 significan figures (B) 3 significan figures (C) 4 significan figures (D) 5 significan figures (E) 7 significan figures. If we were o add o.271 he resul, accouning for significan figures, should be rounded o he neares (E) enh: 10 (A) uni: 14 (B) enh: 13.8 (C) hundredh: (D) housandh: posiion A B C D. For he posiion graph shown, and he 4 inervals A, B, C and D, wha is he correc ranking of velociy? (A) A>B>C>D (B) C>B>D>A (C) A>C>B>D (D) D>A>B>C (E) none of he above. An auomobile can have velociy owards he wes and acceleraion owards he eas (A) if i is speeding up. (B) if i is slowing down. (C) if i is urning souh. (D) if i is going of a cliff. (E) never.. The velociy- graph shown a righ indicaes an objec which (A) is moving a consan velociy in he posiive direcion, and hen acceleraes in he negaive direcion, coming o res. (B) is moving in he posiive direcion wih posiive acceleraion and hen has a larger acceleraion in he negaive direcion, coming o res. (C) is moving in he posiive direcion wih posiive acceleraion and hen has a smaller acceleraion in he negaive direcion, coming o res. (D) is moving in he posiive direcion wih negaive acceleraion and hen has a larger acceleraion in he negaive direcion, coming o res. velociy T i m e 2

3 posiion posiion posiion posiion Velociy aceleraion aceleraion aceleraion aceleraion Velociy Physics 211 Sample quesions for Exam I Spring The displacemen- graph shown a righ indicaes an objec (A) which is moving a consan velociy in he posiive direcion, which hen acceleraes in he opposie direcion, coming o res. (B) which is iniially saionary, hen begins acceleraing in he negaive direcion. (C) which is iniially moving a consan velociy, and hen acceleraes in he posiive direcion.. (D) is a res a all s. Time Displacemen. For he velociy- graph shown a righ, which of he graphs below could be he corresponding acceleraion- graph? (A) (B) (C) (E) none of he above (D). For he velociy- graph shown a righ, which of he graphs below could be he corresponding posiion- graph? (A) (B) (C) (E) none of he above (D) 3

4 posiion posiion posiion posiion aceleraion Physics 211 Sample quesions for Exam I Spring For he acceleraion- graph shown a righ, which of he graphs below could be he corresponding posiion- graph? (A) (B) (C) (D) (E) none of he above Which of he following ses of posiion, velociy and acceleraion versus graphs could acually describe he one dimensional moion of an objec? (A) (B) (C) (D) 4

5 .Which of he following ses of posiion, velociy and acceleraion versus graphs could acually describe he one dimensional moion of an objec? (A) (B) (C) (D) x x x x v v v v a a a a. Two objecs moving wih consan acceleraion saring from res are o cover he same disance. If he second is o cover ha disance in half he would need (A) a quarer of he firs s acceleraion. (B) a half of he firs s acceleraion. (C) wice he firs s acceleraion. (D) four s he firs s acceleraion.. If an objec sars from res and undergoes consan acceleraion hen he disan i covers in 9 seconds, compared o he disance i covers in 3 seconds, will be (A) 1.5 s as grea. (B) 3 s as grea. (C) 4.5 s as grea. (D) 9 s as grea. (E) more informaion is required o make such a comparison.. The posiion of a paricle is given by x = b 2 + c + d where b, c and d are consans and is he. The paricle is (A) saionary. (B) has consan velociy. (C) has consan acceleraion. (D) is undergoing circular moion. 5

6 . The posiion of a paricle is given by x = c + d where c and d are non-zero consans and is he. The paricle is (A) saionary. (B) has consan velociy. (C) has consan acceleraion. (D) is undergoing circular moion.. The velociy of a paricle (moving along he posiive x axis) is given by v = b 2 + c + d where b, c and d are consans and is he. The paricle is (A) saionary. (B) has consan velociy. (C) has consan acceleraion. (D) is undergoing uniform circular moion.. The acceleraion of a paricle is given by a = b 2 + c + d where b, c and d are consans and is he. The paricle is (A) saionary. (B) has consan velociy. (C) has consan acceleraion. (D) is undergoing circular moion.. An objec is hrown verically upward wih some iniial speed. A he insan i reaches maximum heigh (A) he acceleraion is zero. (B) he velociy is zero. (C) he velociy and acceleraion are zero. (D) he acceleraion changes from posiive o negaive. A one insan in Ball A hrown upwards, and ball B is hrown downwards from he same heigh and wih he same speed. Then (A) ball A will reach he ground firs, bu boh balls will have he same speed a he s of heir respecive impacs. (B) ball B will reach he ground firs, bu boh balls will have he same speed a he s of heir respecive impacs. (C) ball A and ball B will reach he ground simulaneously,. and boh balls will have he same speed a he s of heir respecive impacs. (D) ball B will reach he ground firs, and have a larger final speed. (E) ball A will reach he ground firs, and have a larger final speed... The difference beween a vecor and a scalar is ha (A) a scalar only has direcion while a vecor has magniude and direcion. (B) a scalar is jus a number while a vecor has magniude and direcion. (C) a vecor only has direcion while a scalar has magniude and direcion. (D) a vecor is jus a number while a scalar has magniude and direcion. (E) vecors are physical quaniies, while scalars are absrac quaniies. 6

7 . If wo vecors are perpendicular hen (A) he scalar produc (do produc) beween he vecors is zero. (B) he vecor produc (cross produc) beween he vecors is zero. (C) boh he vecor and scalar producs are zero. (D) he vecor and scalar producs are no zero bu are equal o each oher. (E) none of he above. If wo vecors are parallel hen (A) he scalar produc (do produc) beween he vecors is zero. (B) he vecor produc (cross produc) beween he vecors is zero. (C) boh he vecor and scalar producs are zero. (D) he vecor and scalar producs are no zero bu are equal o each oher. (E) none of he above. Two vecors V 1 and V 2 are shown a righ. The vecor which mos closely represens he vecor sum V 1 + V 2 is V 1 (A) (C) V 2 (B) (D) (E) None of he above. which of he following are legiimae mahemaical expressions? (A) 5 a b (B) a b 5 (C) 5 a b (D) a b c (E) a b c. Which of he following is no a vecor quaniy? (A) speed. (B) disance. (C) emperaure. (D) mass. (E) all of he above 7

8 . The figure above shows 6 scenarios for he vecors V1 and V2. The magniude of V1 is 2 unis and he magniude of V2 is 1.5 unis. Rank he six scenarios above by he corresponding do produc (he scalar produc) beween he vecors. (A) A>B>C>D>E>F. (B) E>B=C>F>A>D. (C) D>A>F>B=C>E. (D) B=C=F>E>A>D. (E) F>C=D>B=E=A. The figure above shows 6 scenarios for he vecors V1 and V2. In each scenario, he vecors are eiher righ on a ic mark or exacly halfway beween adjacen ick marks. The magniude of V1 is 2.0 unis and he magniude of V2 is 3.5 unis. The vecor produc (a.k.a. he cross produc) is in par a measure of how perpendicular wo vecors are. Rank he six scenarios above by he corresponding magniude of heir cross producs. The order is (from greaes o leas) (A) B > F = E = C > A > D. (B) D > A > C = E = F > B. (C) B > F > C > E > D > A. (D) A > D > E = C = F > B. (E) none of he above. 8

9 . Suppose an objec such as a seel bearing projecile moion A rolls off of a perfecly horizonal able. 1 B The curve in he figure a righ which 0.9 C bes represens he acual rajecory of 0.8 D he objec is 0.7 y coordinae x coordinae. Ball A hrown horizonally, and ball B is dropped from he same heigh a he same. Then (A) ball A will reach he ground firs. (B) ball B reach will reach he ground firs. (C) ball A and ball B will reach he ground simulaneously. (D) which ever ball is heavier will reach he ground firs.. Two girls decide o jump off a diving board. Kaherine seps off he diving board. Anna runs sraigh off he diving board so ha her iniial velociy is solely horizonal. They boh leave he diving board a he same. Which one lands in he waer firs? (A) Anna. (B) Kaherine. (C) hey hi he waer simulaneously. (D) we need o know Anna's iniial speed o figure his ou. (E) we need o know he heigh of he board o figure his ou.. Bulle A is fired horizonally from a gun and a he same insan bulle B is dropped from same heigh. Then, if air resisance can be negleced (A) bulle A will reach he ground firs. (B) bulle B reach will reach he ground firs. (C) bulle A and bulle B will reach he ground simulaneously. (D) which ever bulle is heavier will reach he ground firs.. Two girls decide o jump off a diving board. Kaherine seps off he diving board. Anna runs sraigh off he diving board so ha her iniial velociy is solely horizonal. They boh leave he diving board a he same. Which one lands in he waer firs?n (A) Anna. (B) Kaherine. (C) hey hi he waer simulaneously. (D) we need o know Anna's iniial speed o figure his ou. (E) we need o know he heigh of he board o figure his ou. 9

10 . A fearless huner akes aim direcly a a monkey hanging from a ree branch. A exacly he insan he fires he gun, he monkey les go of he branch. The bulle (A) passes harmlessly over he falling monkey. (B) is affeced by graviy in he same way as he falling monkey, and so srikes he monkey. (C) passes harmlessly beneah he falling monkey.. (D) more deails are required o deermine wha will happen.. The shape of a projecile's pah is (A) hyperbolic. (B) linear. (C) parabolic. (D) cubic. (E) circular.. Dr. G rips over he compuer car in he fron of he room and launches his (forunaely empy) coffee cup upward and ouward as a projecile. A he insan i reaches maximum heigh (A) he acceleraion is zero. (B) he velociy is zero. (C) he velociy and acceleraion are zero. (D) he verical componen of velociy is zero (E) he horizonal componen of acceleraion becomes negaive.. A car is making a lef urn while following a circular pah and raveling a a consan speed. A he insan he car s velociy is direced norh, he car s acceleraion is direced (A) norh. (B) souh. (C) eas. (D) wes. (E) nowhere, since he speed is consan, he acceleraion is zero! N W E S. A ferris wheel undergoes uniform circular moion, couner clockwise as shown a righ. For a car which is a his insan a he boom, he direcion of he car's acceleraion is (A) up. (B) o he righ. (C) o he lef. (D) down. (E) a an angle up and o he lef. 10

11 . The figure below shows four pahs for an objec. Which of hese pahs could correspond o an objec undergoing consan acceleraion? (A) (B) (C) (D) (E) None of he pahs could correspond o moion under consan acceleraion. 11

12 Par II Problems Show all work. No work = no credi! (15 poins each) Two cars, A and B, boh move along he x-axis. The figure shown is a graph of he posiions of he wo cars versus. A) A wha s, if any, do A and B have he same posiion? B) A wha s, if any, do A and B have he same velociy? C) A wha s, if any, does A pass B? D) A wha s, if any, does B pass A? E) Wha is he acceleraion of A? F) Wha is he acceleraion of B? Posiion versus for A and B A B A cerain graceful physics professor iniially moving a 6.00 m/s across he fron of he room comes o res in a disance of 1.50m (afer colliding wih a cerain wase paper baske). (A) Wha is his acceleraion (aking he iniial direcion of his moion as he posiive direcion )? (B) How much did i ake him o pu on he brakes and come o res? A lunar decen module is making a landing on he surface of he moon. The rockes slow he descen of he module unil i is 4.00 m above he surface of he moon and has a downward speed of m/s a which poin he engines are cu off and he module is in free fall. Noe ha he acceleraion of graviy on he surface of he moon is 1.60 m/s 2. A) Wha is he speed of he module as i ouches he surface of he moon? B) How much elapses from he poin of engine cu off unil he module ouches down? A car wais on an enrance ramp of a freeway for a break in he highway raffic. As an opening appears, he driver acceleraes a a consan rae down he 150 m ramp, reaching he highway raffic's speed of 25 m/s. A) Wha is he acceleraion of he car? B) How long does i ake for he car o make i down he ramp? C) How far does he raffic move in his? (Remember, raffic is moving along a he consan speed of 25 m/s.) Sir Galahad is accidenally fired sraigh up from a caapul. He reaches a maximum aliude of 100 m. (A) Wha is he iniial speed of Sir Galahad as he was launched from he caapul? Meanwhile, Zoo is sanding a a balcony 20 m above ground level a he nearby Casle Anhrax. (B) A wha (relaive o launch) does Sir Galahad pass Zoo on his way up? (C) A wha does Sir Galahad pass Zoo on his way down? 12

13 A mooris raveling wih a consan speed of 15.0 m/s (abou 34 mph) in a 25 mph zone passes a police cruiser which is a res along side he road. Two seconds afer he mooris passes he cruiser ses off in ho pursui wih a consan acceleraion of 4.00 m/s 2. A) How much disance has he mooris gone before he pursui begins? B) How much elapses from he he cruiser sars ill he cruiser caches up o he mooris? C) How far from he cruiser s saring poin are hey when he cruiser caches up o he mooris? D) How fas is he cruiser going when i caches up o he mooris? A mooris raveling wih a consan speed of 20.0 m/s (abou 45 mph) in a 15 mph zone passes a police cruiser which is a res along side he road. A he insan he mooris passes he cruiser ses off in ho pursui wih a consan acceleraion of 4.00 m/s 2. A) How much disance has he mooris gone before he pursui begins? B) How much elapses from he he cruiser sars ill he cruiser caches up o he mooris? C) How far from he cruiser s saring poin are hey when he cruiser caches up o he mooris? In The Fellowship of he Ring, he hobbi Peregrine Took (Pippin for shor) drops a rock ino a well while he ravelers are in he caves of Moria. This wakes a balrog (a bad hing) and causes all kinds of rouble. Pippin heard he rock hi he waer 7.5 s afer he dropped i. a. Ignoring he i ook he sound o ge back up, how deep i he well? b. If he speed of sound is 340 m/s (i was prey cool in ha par of Moria), was i OK o ignore he i akes sound o ge back up? Discuss and suppor your answer wih a calculaion. Dr Gallis is visiing a friend in a highrise building, and umbles ou an open window. He falls 25.0 m ono a 1.50 m all venilaion duc, which is hen crushed fla, bringing Dr. Gallis o res. A) Wha is his speed when he his he venilaion duc? B) Wha is his acceleraion as he crushes he venilaion duc, assuming consan acceleraion? C) Given ha a survivable shor duraion acceleraion would be abou 20 o 25 g's, did Dr Gallis have a chance a surviving his fall? Back your claim wih calculaions A suden in search of he locaion of his physics miderm wanders 100m Norh, hen 150m 40º Norh of Eas, and finally 220m 30º Wes of Norh. (A) Wha is are he Norh and Eas componens of he sudens ne displacemen? (B) Take eas as he posiive x direcion and norh as he posiive y direcion, express he ne displacemen in uni vecor noaion. (C) Deermine he magniude and direcion of he sudens ne displacemen. 13

14 Two vecors A and B are as shown a righ A) Wrie boh vecors in uni vecor noaion y B) Deermine he magniude and direcion of he vecor sum A+B C) Deermine he value of he scalar produc A B D) Deermine he componens of he vecor produc A B and wrie he resul using uni vecors 37º A (15.0 m) x B (20.0 m) 10º Two vecors A and B are as shown a righ. The magniude of A is 3 unis and he magniude of B is 2 unis. A) Wrie boh vecors in uni vecor noaion B) Deermine he magniude and direcion of he vecor sum A+B C) Deermine he value of he scalar produc A B D) Deermine he componens of he vecor produc A B and wrie he resul using uni vecors A B Vecor A is shown a righ. The magniude of A is 3 unis. Vecor B, when wrien in uni vecor noaion is B=4 i 3 j y (A) Wrie vecor A in uni vecor noaion and draw vecor B in he figure (B) Deermine he magniude and direcion of he vecor sum A+B (C) Deermine he value of he scalar produc A B (D) Deermine he componens of he vecor produc A B and wrie he resul using uni vecors 30 A x A cerain projecile launcher has a maximum range on he surface of he earh of 5.00 m when launching a projecile across a horizonal surface. (A) A wha speed does his projecile launch is projeciles? (B) Wha is he maximum heigh his launcher can fire projeciles when aimed direcly upwards? (C) Wha is he maximum range of his launcher on he surface of Mars, where he local acceleraion of graviy is 3.72 m/s 2? (D) Wha is he maximum heigh his launcher can fire projeciles when aimed direcly upwards from he surface of Mars? 14

15 An objec is hrown ou of a window 3.00 m above he ground, a an angle of 30º above he horizonal. The mass his he ground 5.00 m from he wall. (A) Skech he rajecory of he objec. (B) How long is he objec in he air before i his he ground? (C) Wha is he iniial speed of he objec? (D) Wha is he maximum heigh above he ground of he objec during is fligh? A beloved coffee mug slides (horizonally) off of a 1.00 m high lab bench, and lands (mercifully inac) on he ground.750 m away. (A) How long is he mug in he air before sriking he ground? (B) Wha is he final verical componen of velociy? (C) Wha is he horizonal componen of velociy? A mass is hrown ou of a window 5.00 m above he ground wih a speed of 15 m/s a an angle of 20º above he horizonal. (A) Wha are he horizonal and verical componens of he iniial velociy? (B) How long is he objec in he air before i his he ground? (C) Wha is he horizonal disance from he building o he poin of impac? A blunderbuss (a primiive canon) can fire a slug 120m verically upward. (A) Wha is he speed of he slug as i is fired from he blunderbuss? (B) How long is i in he air when fired verically upward? (C) Wha is he speed of he slug when i his he ground? A spring loaded projecile launcher can fire a seel ball bearing a horizonal disance of 3.00 m when fired horizonally from a able 1.20 m high. A) How long is he projecile in he air? B) Wha is he speed of he projecile as i emerges from he h launcher? The launcher is now srapped o an angle bracke so ha he projecile is launched a an angle of 30º from a heigh of m above he ground. C) How long is he projecile in he air? D)How far from he launcher does he projecile land? h d d A ball rolls along a fricionless floor iniially a 2.50 m/s (in he x direcion). A cross wind gives he ball an acceleraion of 1.50 m/s 2 (in he y direcion). The ball is 3.00 m from he edge of he smooh secion of floor. (A) How much does i ake he ball o roll o he edge of he smooh secion of floor? (B) How far down he floor (in he x direcion) does he ball go before reaching he edge? y 3.00 m acceleraion x iniial velociy 15

16 A waer balloon is observed o emerge from an open window of a gymnasium. The window is 5.00 m above he ground. Through miracles of echnology (involving doppler radar and auomaed video analysis), i is deermined ha he balloon leaves he window wih a speed of 16.0 m/s a an angle of 60.0 above he horizonal. (A) How much elapses from when he balloon is passing hrough he window o when i his he ground? (B) How far from he wall does he balloon hi he ground? I is deermined ha someone wihin he gymnasium hrew he balloon from he floor level of he gymnasium, which is level wih he ground ouside. (C) Assuming he launch poin is from he floor level, how far from he wall was he balloon launched? inside ouside 60 wall A waer balloon launcher can launch a waer balloon wih an iniial speed of 30.0 m/s. I is o be used o launch a balloon a a arge which is 80.0 m from he launch poin, a exacly he same heigh as he launcher. A) Wha wo angles (relaive o he horizon) can be used o launch he balloon so ha is rajecory would carry i o he desired impac poin a he range of 80.0 m? B) An obsacle 15.0 m all is placed 30.0 m from he launch poin. Calculae he heigh of he rajecories a his disance in order o deermine which of he rajecories clears he obsacle. 16