KINEMATICS IN ONE DIMENSION

Transcription

1 chaper KINEMATICS IN ONE DIMENSION Secion 2.1 Displacemen Secion 2.2 Speed and Velociy 1. A paricle ravels along a curved pah beween wo poins P and Q as shown. The displacemen of he paricle does no depend on (a) he locaion of P. (b) he locaion of Q. (c) he disance raveled from P o Q. (d) he shores disance beween P and Q. (e) he direcion of Q from P. P Q 2. For which one of he following siuaions will he pah lengh equal he magniude of he displacemen? (a) A jogger is running around a circular pah. (b) A ball is rolling down an inclined plane. (c) A rain ravels 5 miles eas before i sops. I hen ravels 2 miles wes. (d) A ball rises and falls afer being hrown sraigh up from he earh's surface. (e) A ball on he end of a sring is moving in a verical circle. 3. Which one of he physical quaniies lised below is no correcly paired wih is SI uni and dimension? Quaniy Uni Dimension (a) velociy m/s [L]/[T] (b) pah lengh m [L] (c) speed m/s [L]/[T] (d) displacemen m/s 2 [L]/[T] 2 (e) speed ime m [L] 4. A car ravels in a sraigh line covering a oal disance of 9. miles in 6. minues. Which one of he following saemens concerning his siuaion is necessarily rue? (a) The velociy of he car is consan. (b) The acceleraion of he car mus be non-zero. (c) The firs 45 miles mus have been covered in 3. minues. (d) The speed of he car mus be 9. miles per hour hroughou he enire rip. (e) The average velociy of he car is 9. miles per hour in he direcion of moion. 5. A ime = s, an objec is observed a x = m; and is posiion along he x axis follows his expression: x = 3 + 3, where he unis for disance and ime are meers and seconds, respecively. Wha is he objec s displacemen x beween = 1. s and = 3. s? (a) +2 m (c) +1 m (e) 2 m (b) 2 m (d) +2 m

2 12 Chaper 2 Kinemaics in One Dimension Quesions 6 and 7 perain o he siuaion described below: ime (s) posiion (cm) Peer noiced a bug crawling along a meer sick and decided o record he bug s posiion in five-second inervals. Afer he bug crawled off he meer sick, Peer creaed he able shown Wha is he displacemen of he bug beween =. s and = 2. s? (a) cm (c) cm (e) cm (b) 39.9 cm (d) 16.1 cm Wha is he oal disance ha he bug raveled beween =. s and = 2. s? Assume he bug only changed direcions a he end of a five-second inerval. (a) 39.9 cm (c) 16.1 cm (e) 26.5 cm (b) 65.7 cm (d) 47.1 cm 8. In he process of delivering mail, a posal worker walks 161 m, due eas from his ruck. He hen urns around and walks 194 m, due wes. Wha is he worker s displacemen relaive o his ruck? (a) 33 m, due wes (c) 194 m, due wes (e) 355 m, due wes (b) 33 m, due eas (d) 252 m, due eas 9. A Canadian goose flew 845 km from Souhern California o Oregon wih an average speed of 3.5 m/s. How long, in hours, did i ake he goose o make his journey? (a) 27.7 h (c) 66.1 h (e) 7.7 h (b) 8.33 h (d) 462 h 1. When he oudoor emergency warning siren a Cheryl s school was esed, he sound from he siren ook 7. s o reach her house locaed 2.4 km from he school. Wha is he speed of sound in air? (a) 24 m/s (c) 44 m/s (e) 64 m/s (b) 34 m/s (d) 54 m/s 11. A bus leaves New York Ciy, akes a non-direc roue and arrives in S. Louis, Missouri 23 hours, 16 minues laer. If he disance beween he wo ciies is 125 km, wha is he magniude of he bus average velociy? (a) 37.2 km/h (c) 46. km/h (e) 58.1 km/h (b) 41.4 km/h (d) 53.7 km/h 12. Carole s hair grows wih an average speed of m/s. How long does i ake her hair o grow.3 m? Noe: 1 yr = s. (a) 1.9 yr (c).37 yr (e) 2.7 yr (b) 1.3 yr (d) 5.4 yr 13. Carl Lewis se a world record for he 1.-m run wih a ime of 9.86 s. If, afer reaching he finish line, Mr. Lewis walked direcly back o his saring poin in 9.9 s, wha is he magniude of his average velociy for he 2. m? (a) m/s (c) 1.98 m/s (e) 1.1 m/s (b) 1.1 m/s (d) 5.6 m/s

3 Physics, 7e TEST BANK During he firs 18 minues of a 1.-hour rip, a car has an average speed of 11 m/s. Wha mus he average speed of he car be during he las 42 minues of he rip be if he car is o have an average speed of 21 m/s for he enire rip? (a) 21 m/s (c) 25 m/s (e) 29 m/s (b) 23 m/s (d) 27 m/s 15. A urle akes 3.5 minues o walk 18 m oward he souh along a desered highway. A ruck driver sops and picks up he urle. The driver akes he urle o a own 1.1 km o he norh wih an average speed of 12 m/s. Wha is he magniude of he average velociy of he urle for is enire journey? (a) 3.6 m/s (c) 6. m/s (e) 11 m/s (b) 9.8 m/s (d) 2.6 m/s Quesions 16 hrough 19 perain o he siuaion described below: A racecar, raveling a consan speed, makes one lap around a circular rack of radius r in a ime. Noe: The circumference of a circle is given by C = 2πr. 16. When he car has raveled halfway around he rack, wha is he magniude of is displacemen from he saring poin? (a) r (c) πr (e) zero meers (b) 2r (d) 2πr 17. Wha is he average speed of he car for one complee lap? (a) r πr (c) (b) 2r 2πr (d) (e) zero meers/second 18. Deermine he magniude of he average velociy of he car for one complee lap. (a) r πr (c) (e) zero meers/second (b) 2r 2πr (d) 19. Which one of he following saemens concerning his car is rue? (a) The displacemen of he car does no change wih ime. (b) The insananeous velociy of he car is consan. (c) The average speed of he car is he same over any ime inerval. (d) The average velociy of he car is he same over any ime inerval. (e) The average speed of he car over any ime inerval is equal o he magniude of he average velociy over he same ime inerval. Secion 2.3 Acceleraion 2. In which one of he following siuaions does he car have a wesward acceleraion? (a) The car ravels wesward a consan speed. (b) The car ravels easward and speeds up. (c) The car ravels wesward and slows down. (d) The car ravels easward and slows down. (e) The car sars from res and moves oward he eas.

4 14 Chaper 2 Kinemaics in One Dimension 21. An elevaor is moving upward wih a speed of 11 m/s. Three seconds laer, he elevaor is sill moving upward, bu is speed has been reduced o 5. m/s. Wha is he average acceleraion of he elevaor during he 3. s inerval? (a) 2. m/s 2, upward (c) 5.3 m/s 2, upward (e) 2.7 m/s 2, downward (b) 2. m/s 2, downward (d) 5.3 m/s 2, downward 22. A landing airplane makes conac wih he runway wih a speed of 78. m/s and moves oward he souh. Afer 18.5 seconds, he airplane comes o res. Wha is he average acceleraion of he airplane during he landing? (a) 2.11 m/s 2, norh (c) 4.22 m/s 2, norh (e) 14.3 m/s 2, norh (b) 2.11 m/s 2, souh (d) 4.22 m/s 2, souh 23. A picher delivers a fas ball wih a velociy of 43 m/s o he souh. The baer his he ball and gives i a velociy of 51 m/s o he norh. Wha was he average acceleraion of he ball during he 1. ms when i was in conac wih he ba? (a) m/s 2, souh (c) m/s 2, norh (e) m/s 2, norh (b) m/s 2, norh (d) m/s 2, souh 24. A car is moving a a consan velociy when i is involved in a collision. The car comes o res afer.45 s wih an average acceleraion of 65. m/s 2 in he direcion opposie ha of he car s velociy. Wha was he speed, in km/h, of he car before he collision? (a) 29.2 km/h (c) 8.5 km/h (e) 144 km/h (b) 44.8 km/h (d) 15 km/h 25. A rain approaches a small own wih a consan velociy of m/s. The operaor applies he brake, reducing he rain s velociy o m/s. If he average acceleraion of he rain during braking is 1.35 m/s 2, for wha elapsed ime does he operaor apply he brake? (a) 8.44 s (c) 3.38 s (e) 1.4 s (b) 12.7 s (d) 5.92 s Secion 2.4 Equaions of Kinemaics for Consan Acceleraion Secion 2.5 Applicaions of he Equaions of Kinemaics 26. Which one of he following is no a vecor quaniy? (a) acceleraion (c) displacemen (e) insananeous velociy (b) average speed (d) average velociy 27. In which one of he following cases is he displacemen of he objec direcly proporional o he elapsed ime? (a) a ball rolls wih consan velociy (b) a ball a res is given a consan acceleraion (c) a ball rolling wih velociy v is given a consan acceleraion (d) a bead falling hrough oil experiences a decreasing acceleraion (e) a rocke fired from he earh's surface experiences an increasing acceleraion 28. Which one of he following saemens mus be rue if he expression x = v + a is o be used? (a) x is consan. (c) is consan. (e) Boh v and are consan. (b) v is consan. (d) a is consan.

5 Physics, 7e TEST BANK Saring from res, a paricle confined o move along a sraigh line is acceleraed a a rae of 5. m/s 2. Which one of he following saemens accuraely describes he moion of his paricle? (a) The paricle ravels 5. m during each second. (b) The paricle ravels 5. m only during he firs second. (c) The speed of he paricle increases by 5. m/s during each second. (d) The acceleraion of he paricle increases by 5. m/s 2 during each second. (e) The final speed of he paricle will be proporional o he disance ha he paricle covers. 3. Which one of he following siuaions is no possible? (a) A body has zero velociy and non-zero acceleraion. (b) A body ravels wih a norhward velociy and a norhward acceleraion. (c) A body ravels wih a norhward velociy and a souhward acceleraion. (d) A body ravels wih a consan velociy and a ime-varying acceleraion. (e) A body ravels wih a consan acceleraion and a ime-varying velociy. 31. A ruck acceleraes from res a poin A wih consan acceleraion of magniude a and, subsequenly, passes poins B and C as shown in he figure. a MOVE -IT x A B C The disance beween poins B and C is x, and he ime required for he ruck o ravel from B o C is. Which expression deermines he average speed of he ruck beween he poins B and C? (a) v 2 = 2ax (c) v = x (e) v = a x (b) v = (d) 2 v = 1 a Two objecs A and B accelerae from res wih he same consan acceleraion. Objec A acceleraes for wice as much ime as objec B, however. Which one of he following saemens is rue concerning hese objecs a he end of heir respecive periods of acceleraion? (a) Objec A will ravel wice as far as objec B. (b) Objec A will ravel four imes as far as objec B. (c) Objec A will ravel eigh imes furher han objec B. (d) Objec A will be moving four imes faser han objec B. (e) Objec A will be moving eigh imes faser han objec B. 33. Two cars ravel along a level highway. I is observed ha he disance beween he cars is increasing. Which one of he following saemens concerning his siuaion is necessarily rue? (a) The velociy of each car is increasing. (b) A leas one of he cars has a non-zero acceleraion. (c) The leading car has he greaer acceleraion. (d) The railing car has he smaller acceleraion. (e) Boh cars could be acceleraing a he same rae. 34. A car, saring from res, acceleraes in a sraigh-line pah a a consan rae of 2.5 m/s 2. How far will he car ravel in 12 seconds? (a) 18 m (c) 3 m (e) 4.8 m (b) 12 m (d) 15 m

6 16 Chaper 2 Kinemaics in One Dimension 35. An objec moving along a sraigh line is deceleraing. Which one of he following saemens concerning he objec s acceleraion is necessarily rue? (a) The value of he acceleraion is posiive. (b) The direcion of he acceleraion is in he same direcion as he displacemen. (c) An objec ha is deceleraing has a negaive acceleraion. (d) The direcion of he acceleraion is in he direcion opposie o ha of he velociy. (e) The acceleraion changes as he objec moves along he line. 36. A car sars from res and acceleraes a a consan rae in a sraigh line. In he firs second he car covers a disance of 2. meers. How fas will he car be moving a he end of he second second? (a) 4. m/s (c) 2. m/s (e) 8. m/s (b) 16 m/s (d) 32 m/s 37. A car sars from res and acceleraes a a consan rae in a sraigh line. In he firs second he car covers a disance of 2. meers. How much addiional disance will he car cover during he second second of is moion? (a) 2. m (c) 6. m (e) 13 m (b) 4. m (d) 8. m 38. A car is iniially raveling a 5. km/h. The brakes are applied and he car sops over a disance of 35 m. Wha was magniude of he car's acceleraion while i was braking? (a) 2.8 m/s 2 (c) 36 m/s 2 (e) 9.8 m/s 2 (b) 5.4 m/s 2 (d) 71 m/s The minimum akeoff speed for a cerain airplane is 75 m/s. Wha minimum acceleraion is required if he plane mus leave a runway of lengh 95 m? Assume he plane sars from res a one end of he runway. (a) 1.5 m/s 2 (c) 4.5 m/s 2 (e) 7.5 m/s 2 (b) 3. m/s 2 (d) 6. m/s 2 4. A car raveling along a road begins acceleraing wih a consan acceleraion of 1.5 m/s 2 in he direcion of moion. Afer raveling 392 m a his acceleraion, is speed is 35 m/s. Deermine he speed of he car when i began acceleraing. (a) 1.5 m/s (c) 34 m/s (e) 2.3 m/s (b) 7. m/s (d) 49 m/s 41. A rain passes hrough a own wih a consan speed of 16 m/s. Afer leaving he own, he rain acceleraes a.33 m/s 2 unil i reaches a speed of 35 m/s. How far did he rain ravel while i was acceleraing? (a).29 km (c) 1.5 km (e) 3. km (b).53 km (d) 2.3 km 42. A cheeah is walking a a speed of 1.1 m/s when i observes a gazelle 41. m direcly ahead. If he cheeah acceleraes a 9.55 m/s 2, how long does i ake he cheeah o reach he gazelle if he gazelle doesn move? (a) 4.29 s (c) 3.5 s (e) 2.82 s (b) 3.67 s (d) 1.94 s

7 Physics, 7e TEST BANK A body iniially a res is acceleraed a a consan rae for 5. seconds in he posiive x direcion. If he final speed of he body is 2. m/s, wha was he body's acceleraion? (a).25 m/s 2 (c) 4. m/s 2 (e) 1.6 m/s 2 (b) 2. m/s 2 (d) 9.8 m/s A racecar has a speed of 8 m/s when he driver releases a drag parachue. If he parachue causes a deceleraion of 4 m/s 2, how far will he car ravel before i sops? (a) 2 m (c) 4 m (e) 1 m (b) 2 m (d) 8 m 45. A car is sopped a a red raffic ligh. When he ligh urns o green, he car has a consan acceleraion and crosses he 9.1-m inersecion in 2.47 s. Wha is he magniude of he car s acceleraion? (a) 1.77 m/s 2 (c) 3.6 m/s 2 (e) 9.8 m/s 2 (b) 2.98 m/s 2 (d) 7.36 m/s 2 Quesions 46 hrough 48 perain o he siuaion described below: An objec sars from res and acceleraes uniformly in a sraigh line in he posiive x direcion. Afer 11 seconds, is speed is 7. m/s. 46. Deermine he acceleraion of he objec. (a) +3.5 m/s 2 (c) 3.5 m/s 2 (e) +7.7 m/s 2 (b) +6.4 m/s 2 (d) 6.4 m/s How far does he objec ravel during he firs 11 seconds? (a) 35 m (c) 39 m (e) 77 m (b) 77 m (d) 59 m 48. Wha is he average velociy of he objec during he firs 11 seconds? (a) +3.6 m/s (c) +35 m/s (e) 14 m/s (b) +6.4 m/s (d) +72 m/s Secion 2.6 Freely Falling Bodies 49. Ball A is dropped from res from a window. A he same insan, ball B is hrown downward; and ball C is hrown upward from he same window. Which saemen concerning he balls afer heir release is necessarily rue if air resisance is negleced? (a) A some insan afer i is hrown, he acceleraion of ball C is zero. (b) All hree balls srike he ground a he same ime. (c) All hree balls have he same velociy a any insan. (d) All hree balls have he same acceleraion a any insan. (e) All hree balls reach he ground wih he same velociy. 5. A ball is hrown verically upward from he surface of he earh. Consider he following quaniies: (1) he speed of he ball; (2) he velociy of he ball; (3) he acceleraion of he ball. Which of hese is (are) zero when he ball has reached he maximum heigh? (a) 1 and 2 only (c) 1 only (e) 1, 2, and 3 (b) 1 and 3 only (d) 2 only

8 18 Chaper 2 Kinemaics in One Dimension 51. A rock is hrown verically upward from he surface of he earh. The rock rises o some maximum heigh and falls back oward he surface of he earh. Which one of he following saemens concerning his siuaion is rue if air resisance is negleced? (a) As he ball rises, is acceleraion vecor poins upward. (b) The ball is a freely falling body for he duraion of is fligh. (c) The acceleraion of he ball is zero when he ball is a is highes poin. (d) The speed of he ball is negaive while he ball falls back oward he earh. (e) The velociy and acceleraion of he ball always poin in he same direcion. 52. A brick is dropped from res from a heigh of 4.9 m. How long does i ake he brick o reach he ground? (a).6 s (c) 1.2 s (e) 2. s (b) 1. s (d) 1.4 s 53. A ball is dropped from res from a ower and srikes he ground 125 m below. Approximaely how many seconds does i ake he ball o srike he ground afer being dropped? Neglec air resisance. (a) 2.5 s (c) 5.5 s (e) 16. s (b) 3.5 s (d) 12.5 s 54. Waer drips from res from a leaf ha is 2 meers above he ground. Neglecing air resisance, wha is he speed of each waer drop when i his he ground? (a) 3 m/s (c) 4 m/s (e) 2 m/s (b) 15 m/s (d) 1 m/s 55. Elijah hrows a ennis ball verically upward. The ball reurns o he poin of release afer 3.5 s. Wha is he speed of he ball as i is released? (a) m/s (c) 17 m/s (e) 34 m/s (b) 14 m/s (d) 21 m/s 56. A rock is dropped from res from a heigh h above he ground. I falls and his he ground wih a speed of 11 m/s. From wha heigh should he rock be dropped so ha is speed on hiing he ground is 22 m/s? Neglec air resisance. (a) 1.4h (c) 3.h (e).71h (b) 2.h (d) 4.h 57. A 5.-kg rock is dropped from res down a verical mine shaf. How long does i ake for he rock o reach a deph of 79 m? Neglec air resisance. (a) 2.8 s (c) 4.9 s (e) 4. s (b) 9. s (e) 8. s 58. Neglecing air resisance, wha maximum heigh will be reached by a sone hrown sraigh up wih an iniial speed of 35 m/s? (a) 98 m (c) 41 m (e) 18 m (b) 16 m (d) 63 m Quesions 59 hrough 61 perain o he siuaion described below: A ball is sho sraigh up from he surface of he earh wih an iniial speed of 19.6 m/s. Neglec any effecs due o air resisance.

9 Physics, 7e TEST BANK Wha is he magniude of he ball s displacemen from he saring poin afer 1. second has elapsed? (a) 9.8 m (c) 19.6 m (e) 58.8 m (b) 14.7 m (d) 24.5 m 6. Wha maximum heigh will he ball reach? (a) 9.8 m (c) 19.6 m (e) 58.8 m (b) 14.7 m (d) 24.5 m 61. How much ime elapses beween he hrowing of he ball and is reurn o he original launch poin? (a) 4. s (c) 12. s (e) 16. s (b) 2. s (d) 8. s Quesions 62 hrough 65 perain o he saemen below: A ennis ball is sho verically upward in an evacuaed chamber inside a ower wih an iniial speed of 2. m/s a ime = s. 62. How high does he ball rise? (a) 1.2 m (c) 4.8 m (e) 98. m (b) 2.4 m (d) 72.4 m 63. Approximaely how long does i ake he ennis ball o reach is maximum heigh? (a).5 s (c) 4.8 s (e) 9.8 s (b) 2.4 s (d) 6.8 s 64. Deermine he velociy of he ball a = 3. seconds. (a) 9.4 m/s, downward (c) 29.4 m/s, downward (e) 38.8 m/s, downward (b) 9.4 m/s, upward (d) 38.8 m/s, upward 65. Wha is he magniude of he acceleraion of he ball when i is a is highes poin? (a) zero m/s 2 (c) 19.6 m/s 2 (e) 3.13 m/s 2 (b) 9.8 m/s 2 (d) 4.9 m/s 2 Secion 2.7 Graphical Analysis of Velociy and Acceleraion 66. Saring from res, a paricle ha is confined o move along a sraigh line is acceleraed a a rae of 5. m/s 2. Which saemen concerning he slope of he posiion versus ime graph for his paricle is rue? (a) The slope has a consan value of 5. m/s. (b) The slope has a consan value of 5. m/s 2. (c) The slope is boh consan and negaive. (d) The slope is no consan and increases wih increasing ime. (e) The slope is no consan and decreases wih increasing ime.

10 2 Chaper 2 Kinemaics in One Dimension 67. The graph shows he heigh versus ime of an objec. Esimae he insananeous velociy, in m/s, of he objec a ime = 15 min. (a).9 m/s (b).7 m/s (c).5 m/s (d).3 m/s (e).1 m/s Heigh (meers) Time (minues) Quesions 68 hrough 7 perain o he graph below: 1 An objec is moving along he x axis. The graph shows is posiion from he saring poin as a funcion of ime. Various segmens of he graph are idenified by he leers A, B, C, and D. posiion (m) 5 5 A B C D ime (s) 68. During which inerval(s) is he objec moving in he negaive x direcion? (a) during inerval B only (d) during inervals B and D (b) during inervals B and C (e) during inervals B, C, and D (c) during inervals C and D 69. Wha is he velociy of he objec a = 7. s? (a) +3. m/s (c) 2. m/s (e) zero m/s (b) 1. m/s (d) 3. m/s 7. Wha is he acceleraion of he objec a = 7. s? (a) zero m/s 2 (c) 3. m/s 2 (e) +4. m/s 2 (b) 2. m/s 2 (d) +9.8 m/s 2 Quesions 71 hrough 74 perain o he saemen and graph below: 4 D An objec is moving along a sraigh line. The graph shows he objec s posiion from he saring poin as a funcion of ime. posiion (m) B C A E ime (s)

11 Physics, 7e TEST BANK In which segmen(s) of he graph does he objec s average velociy (measured from = s) decrease wih ime? (a) AB only (c) DE only (e) BC and DE (b) BC only (d) AB and CD 72. Wha was he insananeous velociy of he objec a = 4 s? (a) +6 m/s (c) +1 m/s (e) +4 m/s (b) +8 m/s (d) +2 m/s 73. In which segmens(s) of he graph does he objec have he highes speed? (a) AB (c) CD (e) AB and CD (b) BC (d) DE 74. A which ime(s) does he objec reverse is direcion of moion? (a) 1 s and 2 s (c) 1 s (e) 5 s (b) 2 s and 5 s (d) 2 s Quesions 75 hrough 78 perain o he saemen and graph below: An objec is moving along a sraigh line. The graph shows he objec s velociy as a funcion of ime. velociy (m/s) ime (s) 75. During which inerval(s) of he graph does he objec ravel equal disances in equal imes? (a) s o 2 s (d) s o 2 s and 3 s o 5 s (b) 2 s o 3 s (e) s o 2 s, 3 o 5 s, and 5 o 6 s (c) 3 s o 5 s 76. During which inerval(s) of he graph does he speed of he objec increase by equal amouns in equal imes? (a) s o 2 s (d) s o 2 s and 3 s o 5 s (b) 2 s o 3 s (e) s o 2 s, 3 o 5 s, and 5 o 6 s (c) 3 s o 5 s 77. How far does he objec move in he inerval from = o = 2 s? (a) 7.5 m (c) 15 m (e) 25 m (b) 1 m (d) 2 m 78. Wha is he acceleraion of he objec in he inerval from = 5 s o = 6 s? (a) 4 m/s 2 (c) 2 m/s 2 (e) 1 m/s 2 (b) +4 m/s 2 (d) +2 m/s 2

12 22 Chaper 2 Kinemaics in One Dimension Quesions 79 hrough 81 perain o he siuaion described below: 1 An objec is moving along a sraigh line in he posiive x direcion. The graph shows is posiion from he saring poin as a funcion of ime. Various segmens of he graph are idenified by he leers A, B, C, and D ime (s) 79. Which segmen(s) of he graph represen(s) a consan velociy of +1. m/s? (a) A (c) C (e) A and C (b) B (d) D posiion (m) A B C D 8. Wha was he insananeous velociy of he objec a he end of he eighh second? (a) +7.5 m/s (c).94 m/s (e) zero m/s (b) +.94 m/s (d) +1.1 m/s 81. During which inerval(s) did he objec move in he negaive x direcion? (a) only during inerval B (d) during boh inervals C and D (b) only during inerval C (e) The objec never moved in he negaive x direcion. (c) only during inerval D Addiional Problems 82. The rae a which he acceleraion of an objec changes wih ime is called he jerk. Wha is he dimension of he jerk? 2 2 [L] [L] [L] (a) (c) (e) 2 3 [T] [T] [T] (b) [L] 2 [T] (d) [L] 3 [T] 83. In a race, José runs 1. mile in 4.2 min, mouns a bicycle, and rides back o his saring poin, which is also he finish line, in 3.2 min. Wha is he magniude of José s average velociy for he race? (a) zero mi/h (c) 14.9 mi/h (e) 19.9 mi/h (b) 12.1 mi/h (d) 17. mi/h Quesions 84 and 85 perain o he siuaion described below: A mooris ravels due norh a 3 mi/h for 2 hours. She hen reverses her direcion and ravels due souh a 6 mi/h for 1 hour. 84. Wha is he average speed of he mooris? (a) zero mi/h (c) 4 mi/h (e) 6 mi/h (b) 3 mi/h (d) 5 mi/h

13 Physics, 7e TEST BANK Wha is he average velociy of he mooris? (a) zero mi/h (c) 4 mi/h, souh (e) 45 mi/h, souh (b) 4 mi/h, norh (d) 45 mi/h, norh Quesions 86 hrough 88 perain o he saemen below: Saring from res, a paricle confined o move along a sraigh line is acceleraed a a rae of 4 m/s Which saemen accuraely describes he moion of he paricle? (a) The paricle ravels 4 meers during each second. (b) The paricle ravels 4 meers during he firs second only. (c) The speed of he paricle increases by 4 m/s during each second. (d) The acceleraion of he paricle increases by 4 m/s 2 during each second. (e) The final velociy of he paricle will be proporional o he disance ha he paricle covers. 87. Afer 1 seconds, how far will he paricle have raveled? (a) 2 m (c) 1 m (e) 4 m (b) 4 m (d) 2 m 88. Wha is he speed of he paricle afer i has raveled 8 m? (a) 4 m/s (c) 3 m/s (e) 1 m/s (b) 8 m/s (d) 6 m/s Quesions 89 hrough 92 perain o he siuaion described below: A rock, dropped from res near he surface of an amosphere-free plane, aains a speed of 2. m/s afer falling 8. meers. 89. Wha is he magniude of he acceleraion due o graviy on he surface of his plane? (a).4 m/s 2 (c) 2.5 m/s 2 (e) 16 m/s 2 (b) 1.3 m/s 2 (d) 25 m/s 2 9. How long did i ake he objec o fall he 8. meers menioned? (a).4 s (c) 1.3 s (e) 16 s (b).8 s (d) 2.5 s 91. How long would i ake he objec, falling from res, o fall 16 m on his plane? (a).8 s (c) 2.5 s (e) 22 s (b) 1.1 s (d) 3.5 s 92. Deermine he speed of he objec afer falling from res hrough 16 m on his plane. (a) 28 m/s (c) 56 m/s (e) 32 m/s (b) 32 m/s (d) 64 m/s Quesions 93 hrough 97 perain o he siuaion described below: A ennis ball is sho verically upward from he surface of an amosphere-free plane wih an iniial speed of 2. m/s. One second laer, he ball has an insananeous velociy in he upward direcion of 15. m/s.

14 24 Chaper 2 Kinemaics in One Dimension 93. Wha is he magniude of he acceleraion due o graviy on he surface of his plane? (a) 5. m/s 2 (c) 12 m/s 2 (e) 24 m/s 2 (b) 9.8 m/s 2 (d) 15 m/s How long does i ake he ball o reach is maximum heigh? (a) 2. s (c) 4. s (e) 8. s (b) 2.3 s (d) 4.6 s 95. How high does he ball rise? (a) 7. m (c) 5. m (e) 4. m (b) 1. m (d) 2. m 96. Deermine he velociy of he ball when i reurns o is original posiion. Noe: assume he upward direcion is posiive. (a) +2 m/s (c) +4 m/s (e) zero m/s (b) 2 m/s (c) 4 m/s 97. How long is he ball in he air when i reurns o is original posiion? (a) 4. s (c) 8. s (e) 16 s (b) 4.6 s (d) 9.2 s Quesions 98 and 99 perain o he siuaion described below: A small objec is released from res and falls fee near he surface of he earh. Neglec air resisance. 98. How long will i ake o fall hrough he fee menioned? (a) 2.49 s (c) 4.5 s (e) 1. s (b) 3.12 s (d) 6.25 s 99. Approximaely how fas will he objec be moving afer falling hrough he fee menioned? (a) 9.8 f/s (c) 8 f/s (e) 32 f/s (b) 4 f/s (d) 16 f/s Quesions 1 hrough 13 perain o he siuaion described below: The figure shows he speed as a funcion of ime for an objec in free fall near he surface of he earh. The objec was dropped from res in a long evacuaed cylinder. v 1. Which one of he following saemens bes explains why he graph goes hrough he origin? (a) The objec was in a vacuum. (d) All v vs. curves pass hrough he origin. (b) The objec was dropped from res. (e) The acceleraion of he objec was consan. (c) The velociy of he objec was consan.

15 Physics, 7e TEST BANK Wha is he numerical value of he slope of he line? (a) 1. m/s 2 (d) 9.8 m/s 2 (b) 2. m/s 2 (e) This canno be deermined from he informaion (c) 7.7 m/s 2 given since he speed and ime values are unknown. 12. Wha is he speed of he objec 3. seconds afer i is dropped? (a) 3. m/s (b) 7.7 m/s (c) 9.8 m/s (d) 29 m/s (e) This canno be deermined since here is no specified value of heigh. 13. If he same objec were released in air, he magniude of is acceleraion would begin a he free-fall value, bu i would decrease coninuously o zero as he objec coninued o fall. For which one of he choices given does he solid line bes represen he speed of he objec as a funcion of ime when i is dropped from res in air? Noe: The dashed line shows he free-fall under vacuum graph for comparison. (a) (c) (e) v v v (b) (d) v v