DSE Physics - Section B : MC. FMl : Position and Movement PB-FMl-M/03 9. lcm2cm 3cm The diagram above shows a ticket-tape produced by a trolley being pulled by a rubber band. statements about the trolley is/are true ? (1) Its displacement in.creases unifon:nly with time. (2) Its velocity increases uniformly with time. (3) Its acceleration increases unifonnly with time. A. (1) only B. (2) only C. (1) & (2) only D. (2) & (3) only 10. displacement/m 4 --------------------- 2 O .fL'--+----+----+----i--- (tima) 2 / s 2 0 2 3 4 Which of the following An object is accelerated from rest along a straight line. square of time. What is the acceleration of the object? The above graph shows the variation of its displacement with the A. o.sms- 2 B. l.Oms- 2 C. 2.0ms"" 2 D. 4.0ms-2 11. < HKCE 1988 Paper II - 1 > KL g: M ' 16 N I 36 0 I 64 The above figure shows the stroboscopic photograph of a ball rolling down a slope. If the stroboscope m akes 2 flashes per second, in which region does the ball have an average speed of40cms-1 ? A. LM B. MN C. NO D. OP 12. < BKCE 1989 Paper II - 2 > An object is falling from rest with an acceleration of9.8 m s-2. Which of the following statements is/are correct? (1) It falls with a constant spe ed of9.8 ms-1. (2) It falls. 9.8 m every sec ond. (3) Ithasaspeedof19.6ms-1 after2s. A. (1) only B. (3) only C. (1) & (2) only D. (2) & (3) only DSE Physics - Section B : M.C. FM1 : Position and Movement 13. < HKCE1989 Paper II- 3 > PB-FMl-M/04 A particle is thrown vertically upwards. When the particle is at the maximum height, its acceleration is A. zero. B. changing from upwards to downwards . C. pointing upwards. D. pointing downwards. 14. A coin and a f.eather are allowed to fall in a long vertical glass tube from which the air has been evacuated. Which one of the following combinations best descnOes the motion of the coin andthe feather ? Coin A. uniform speed B . uniform acceleration C. uniform acceleration D. uniformacc eleration 15. < HKCE 1990 Paper II - 1 > Feather same uniform speed same uniform acceleration smaller uniform acceleration greater uni.form acceleration The graph shows how the square of velocity of an object undergoing uniform acceleration varies with displacement. The object is initially at rest and travels along a straight line. The acceleration of the object is A. OSms-2 B. l.0ms-2 C. 2.QmS- 2 D. 4.0ms -2 16. < BK.CE 1991Paper II -4 > 4 2 The above figure shows the strobe photog;raph of a ball rollin8 down a slope. of 5 Hz. Find the acceleration ofth e ball A. 0.20ms-2 B. 0.50 m s- 1 C. 0.67mS- 2 D. l.OOms-1 17. The figure shows the ve,ocity-time graph of an object. Whlch of the following statements about the object is/are true? (1) Its acceleration in the first 10 sis 2 m s - 2• (2) The total distance travelled is 250 m. (3) Itretums to its starting point after 25 s. A. (1) only B. (2) only velocity/ m s-1 10 ""'-----+---+--••Im 0 2 3 The stroboscope is flashing at a frequency c. (1) & (3) only D. (2) & (3) only �---1---4--�-..... --~time/ s 0 10 20 30 DSE Physics - Section B : M.C. FMl : Position and Movement 18. < HKCE 1992 Paper II - I> PB-FMl-M/05 Which of the following displacemenMime graphs descnOes the motion of a particle moving in a straight line with uniform deceleration? A. B. C. D. LL. 19. < HJ(CE 1992 Paper II- 2 > B :A. '"' A man takes 2 s to walk from point A to point B, and then takes 3 s to walk froll1 point B to point C, where ABC is an equilateral triangle of side 3 m. Find the magnitude ofhis average VELOCITY :fromA to C. A. 0.60ms-1 B. l.00mS- 1 C. 1.20ms-1 D. 1.25ms-1 20. < BK.CE 1992 Paper Il- 4 > t Velocity/m s"" 1 120 -60 -120 Tim.els The above figure shows a man near the edge ofa cliff projecting a stone vertically upwards. The stone reaches the sea after 18 s. The graph shows the velocity~ time for the motion of the stone. Find the height of the cliff. (Take g = 10 ms- 2 .) A. 180m B. 540m C. 720m D. 900m DSE Physics - Section B : M.C. FMl : Position and Movement 21. PB-FMl-M/06 An object is thrown vertically upwards from a point A. It travels to the highest point B and then falls back to A. Neglecting air resistance, which of the following statements i s/are true? (I) The total displacement of the object is zero. (2) The acceleration of the object is constant throughout themotion. (3) The time for the upwardmotion is longer than the time for the downwardmotion. A. (!) only B. (3) only C. (!) & (2) only D. (2) & (3) only 22. The paper tape shown is obtained from. a trolleymoving with uni£onn acceleration. The frequency of the ticker-tape timer is 50 Hz. Flnd the acceleration ofthe trolley. A 0..2lm� B. o.1omr c. 0.73mr D. I.05m r 23. < BKCE 1993 Paper IT- 5 > I:: I.5 on 4 I�•---- 3.6cm The above dia gram shows the variation of the acceleration of an object which is initially at rest Which of the following velocity-time graphs correctly dcscnOes themotion ofthe object? A v B. .lee, ,. C. D. 24. Aman takes 30 s to walk 80 mtowards the east. He then takes 10 s to run 60 m towards the south. Which ofthe following statements is/are correct? (1) Themagnitude of the resultant displacement of the man is 140 m. (2) The average speed of the IllllD is 4.3m s-1• (3) Themagnitude ofthe average velocity ofthe man is 2.5 m s-1• A. (!) only B. (3) only C. (I) & (2) only D. (2)& (3)onJy DSE Physics - Section B : M.C. FMl : Position and Movement PB-FMl-M/07 25. Velocity / m S- 1 2 0 1 0 0 t-----t------'0,.,. -::- --t--- Time/ s 2 -10 The above diagram. shows the variation of the velocity of an object with time:. What is the distance travelled by the object in the fust 3 seconds ? A. Sm B. 15m C- 25m D. 30m 26. < BKCE 1995 Paper 11 - 4 > 27. :ZS. An object starts from rest and moves with unifutm acceleration along a straight line. Which of the graphs below conceming the motion of the object is/axe correct 'l (s = displacement, v =velocity, t = time) "' o�, "' '�" O A. (1) only B. (!) & (2) only C. (2) & (3) only D. (!), (2) & (3) A man walks 40m towards the west. He then walks 40 m towards the south and lastly walks 70m towards the east Find the magnitude of the resultant displacement of the man. A. 30m B. 40m C. 50m D. 70m An object mc:ives with uniform acceleration along a straight line. Which of the following graphs correctly descnCe(s) the motion ofthe object? ,,, ,�- "',�- 0 E=_,_ A. (1) oilly B. (2) only C. (!) & (3) o,!y D. (2) & (3) o,!y DSE Physics - Section B : MC. F.M:1 : Position and Movement PB-FMl-M/08 29. < HKCE 1997 Paper Il - 2 > A student walks along a curve ABC, which is made up of two semi-circular parts AB and BC of :radius 3 m and 4 m respectively. He takes 2 s to walk from.A to Band 5 s from B to C. Find the magcitude of the average velocity of the student from A to C A. l.0ms-1 B. 2.0ms-1 C. 2.3 ms-1 D. 3.lms-1 30. < BKCE 1997 Paper II- 6 > A -« B e--- ➔ 3m 4m C A particle is released from rest and falls vertically under gravity. Ifthe distance travelled by the particle in the 1st second is x and that travelled in the 2nd second isy, find the ratio x: y. A. 1: 1 B. 1 :2 c. 1 :3 D. 1 :4 31. < HK.CE 1998 Paper II- 2 > A carUI!dergoes uniform deceleration along a straight road. Its velocity decreases from 30 m s-1 to 20m S- 1 after travelling a distance of 100m. How much further will the car travel before it co mes to a rest '1 A. 50m B. 80m C. lSOm D. 200m 32. < HK.CE 1998 Paper II - 4 > o)_/_,_,_,_\_,_, tis 10 20 30� The velocity..fune graph of a car travelling along a straight horizontal road is shown above. shows the variation of the acceleration a of the car with the time t '1 A. a B. a Which ofthe following graphs f---+---+-->---+--+tls f----1---+--+--+-->-tls c. 10 20 0 30 40 f---+---+---+--+-+-->- ti, 3P : 40 10 20 , , ' ' '--' 10 20 D. a f"---+--+--+--+-->-tl, 10 20 i "' DSE Physics - Section B : M.C. FMl : Position and Movement 36. < HKCE 2000 Paper ll- 3 > PB-FMI-M/10 A raoing car accelerates fromrest to a speed ofl00 lanh-1 in 3.2 s. Find the average acceleration ofthe car. A. 4.34ms- 2 B. 8.68 ms- 2 C. 15.63 m s -2 D. 31.25 ms--2 37. A girl walks along a straight road from. a point A to a point B wit:b. an average speed I m s- 1 • She then retums from. B to A along the srune road with an average speed 2 ms- 1• Find the average speed of the girl for the whole joumcy. A. ""'· B. 0.67mS- 1 C. 1.33 ms- 1 D. l.SOms-1 38. Distance from P A car travels along a straight road. The variation of the distance of the car from a fixed point P on the road with time is shown above. Which of the following statements is correct? A The speed of the car is decreasing. B . The car is movin.gtovmds P. C. There is an unbalanced force acting on the car. D. The area under the graph denotes the total distance travelled by the car. 39. < IIKCE 2002 Paper II - I> slm The figure above shows the distance-time graphs of two toy cars P and Q moving along linear track. Which of the following statements is/are correct? (I) Car.Pwillreach the20m-markfust. ( 2 ) Car Pis overtaking car Qatt=S s. (3) The average sp® of car Pin the first 5 sis smaller than that of car Q. A. (!) & (2) only B. 0) & (3) only C. (2) & (3) only D. (!), (2) & (3) DSE Physics - Section B : M.C. FMl : Position and Movement 40. PB-FMl-M/11 A pie<:e of stolle is hung from a balloon, which is rising vertically upward. If the string connecting the stone and the balloon suddenly breaks, which of the following velocity-time graphs represents the subsequent motion of the stone ? (Note : Velocity pointing upward is taken t obe positive.) Questions 41 and 42 : The figure shows the velocity-time graph of a car travelling along a straight r oad. 41. What physical quantity does the area of the shaded region represent? A. ""'"' B .. momentum C. acceleration D. displacement 42. < BKCE 2003 Paper II - 2 > Wlrich of the statements are correct? (1) Th.ecarchanges itsdirectionoftravelat t = t1. (2) The caris farthest away from the starting po:int at t = t1. (3) Thecarretumstoitsstartingpointat t = tz, A. (1) & (2)only B. (1) & (3) only C. (2) & (3) only D. (1),(2)&(3) 43. < HK.CE 2003 Paper n- 3 > A car starts at point A andtravels along a circular path of radius 30 m. After 15 s, the car retums topoint A. Find the average speedof the car within 1his pcriodoftizne. A. "'"' B. 2ms·1 C. 6.3 m s· 1 D. 12.6ms· 1 A - G DSE Physics - Section B : M.C. FMl : Position and Movement 44.. < BKCE 2003 Paper n- 4 > PB-FMl-M/12 A plane starts from rest and accelerates at 2 m s-2• Iftbe mimmum take-off speed i s 60 m s-1, find the minimum distance travelled by theplane before it takes off. A. 450m B. 900m c. 1800m D. 3600m 45. < HKCE2004 Paper n- 3 > " The figure shows the velocity-time graphs of two students P and Q running along a straight r oad. They start at the same point Which of the following statements is/are correct? (1) TheaveragespeedofPbetween t"'O and t=t1 islargerthanthatofQ. (2) At t =ti, P and Q reach the same point (3) At t""t2,QisaheadofP. A. (1) only B. (3) only C. (1) & (2) only D. (2) & (3) only Questions 46 and 47 : Patrick is dr ivingalong a straight horizontal road. At time t = 0, he obser vesthat an accident bas happened. He then applies the brakes to stop his car with uniform deceleration. The graph shows the variation of the speed of the car with time. v/ms-1 14 46. < BKCE 2005Paper Il-1 > What is thereaction time of Patrick? A. - B. 0.8 s C. 4.2 s D. 5.0s 47. < HKCE2005 Paper II-2> Find the distance travelled by the car from time t = 0 to 5.0 s. A. 29.4m B. 40.6m C. 46.2m D. 81.2m DSE Physics - Section B : M.C. FMl : Position and Movement 48. < BKCE 2006 Paper II - 1 > Velocity ,/ J -----;,(, -A ' ______________ J o ""'= '-------T L- ---,►Time PB-FMl-M/13 Two cm A and B start from rest simultaneously and travel along the same sttaight road. The velocity-time graphs of the two cars are shown above. Which of the following statements about the motion of the two cars is/are always correct? (1) A andB have the same average velocity during the time interval Oto T. (2) A and B have the same average acceleration during the time interval Oto T. (3) A andB travel the same displacement during the time interval Oto T. A. (l)only B. (2) only C. (I) & Q) only D. (2) & (3) only 49. < HK.CE 2006 Paper II- 28 > A B A car travels along a straight road from A to B with a uniform acceleration. The speed of the car is v 1 at the instant when m.1f of the journey time from A toB is elapsed and its speed is Vl at the mid-way of A andB. Which of the following is correct? A. vi is always smaller than 111. B. vi is always greater than 112. C. vi and l'2 are always equal. D. Whether v1 is greater than or smaller than l-'2 depends on the initial velocity ofthe car at A. 50, < HK.CE 2006 Paper II - 7 > The acceleration of objects due to gravity on the Moon is about 1/6 that on the Earth. Which of the following diagrams shows the con:ect velocity-time graphs for a free falling object dro pp ing respectively on the Earth's surface and the Moon's '"""''? A a c n 51. < HK.CE 2007 Paper II -1 > V I /Moon // - 0 A bicycle finish.es a 100-metre jou:rney in 9.77 s. Assume that the bicycle starts from rest aoo moves with a llllifonn acceleration. What is the acceleration of the bicycle throughout the journey ? A. l.OSms-2 B. 2.10 ms -2 C. 10.2ms-2 D. 20.Sms-2 DSE Physics M.C. - Section B PB--FM1 -M /14 Force & Motion I Position and Movement 52. The displacement-time graph of an object moving along a straight line is shown below. (07) s 53. (07) Which of the following graphs best represents the relationship between the velocity and time ofthe object ? A B. � D. V V V V -�· -�· .pL, -�· -ci----�-----..... ,lrn The above graph shows the variation of the s111uare of velocity vl with the displacements of a particle moving along a straight line. What is the acceleration of the particle? A. 0.5 m s- 2 B. lms-i C. l.Sms- 2 D. 2ms-i 54. A fish jumps up Vertically to a maximum height of0.5 m above the water surface. (08) surface ? What is the speed when it just leaves the 55. (08) A. 3.J3ms- 1 B. 4.43 m s- 1 C. 6.26m s- 1 D. 9.81 rn s- 1 0 t=?I - Picture (a) ground 0 0 0 � Pieture(b) An experiment is conducted by releasing a stone from rest to the ground. At constant time interval T, the positions of the stone are recorded. Picture (a) shows its positions at different time. Which of the following changes will give a path of the stone as shown in Picture (b)? (Neglect air resistance.) A. A shorter time interval is used. B. A longer time interval is used. C. A lighter stone ls used. D. A heavier stone is used. , DSE Physics - Section B : M.C. FMl : Position and Movement 56. v/ms-1 20,r---------,� 0 � o"'------'10 _____ 20'-+11' PB-FMl-M/15 At t = 0, a car and a truck are at the same point on a horizontal straight road. Their velocity - time graph is shown in the figure above. Which ofthe following statements is correct? At t = 10 s, the caris 100 m behind the truck, ,.., At t = 10 s, the car catches up the truck. At t = 20 s, the car is 100 m behind the truck. At t = 20 s, the car catches up the truck. 57. John and Mary a:re driving two cars, P and Q, along a straight horizontal road respectively. At time t = 0, they both see an obstacle and apply the brakes to stop the cars with uniform deceleration. The variation of velocity with time ofthe two cars is shown in the figure below. Which of the following statements is/are correct? {l) The two cars have the same initial speeds. (2) The reaction times ofJohn and Mary are the same. (3) The total stopping distances oftbe two cars are the same. (2) only (3) only (!) & (2) only (!) & (3) only 58. < HKCE 2009 Paper Il- 1 > v/ms·1 A car is travelling at a constant speed of50 kmh-1• How much time does it take to travel 500 m? 0.1 s 10, 36' 360 s 59. x&P , P, P, y The figure above shows three paths Pi, P2 and Pl fromXto Yon a horizontal plane. Three students take the same time to travel fromX to Y via the th.rec paths respectively. Which of the following physical quantities about their joumey is/are the same? (I) ru,p1'oonont (2) distance (3) average speed (1) only (2) only (I) & (3) only (2) & (3) only . DSE Physics - Section B : M.C. FMl : Position and Movement PB-FMl-M/16 60. < BKCE 2009 Paper Il -28 > 61. A diver jumps up vertically in the air from a high platform and falls into water. The v-t graph below shows the variation of the velocity of the diver against time from the point he jumps (P) until he is at the lowest point (Q) in 1he water. platform p --- ----------- �= Q ,=: = : = : = : = : = : = : = : = : = : = : --------------- Which of the following is correct ? not to scale total distance travelled from P to Q A, s.9m G,.. I0.6m C.-. 11.5 m D .. 11.sm < BKCE 2010 Paper ll-1 > 3 0 ,_ _ _,,,________ 1._6--r2 -+ ti, 0.3 -13 height of the platform above water surface Sm !Om Sm 10.6m Mary walks-along a triangularpathXJ'Zwhere XY= YZ'= ZK. It takes her 10 s, 20 sand 10 s to travel tbroughXY, YZ' and ZX' respeetively. Which of the following graphs best represents the variation of distance travelled with time? A, Distance/ m C � Distance / m {) ... Distance / m Distance /m 0 10 20 30 40 DSE Physics M.C. - Section B PB - FMl - M / 17 Force & Motion I Position and Movement M62 An obje<:t of mass m, released from rest at height h above the ground, talces time t rorcach the ground. If another object of (11) mass 2 m is released from rest at the same height, how long does it take to reach the ground? (}feglect air resistance.) M63. (11) A. t B. C. I D. ✓2, "- The graph above shows the velocity�time graph of an object which is thrown vertically upwards under gravity. Jfthe object is thrown vertically upwards with a higher initial velocity, which ofthe following graphs (in dotted lines) best represents the expected result? (Neglect air resistance.) A. C v/ms-1 D. DSE Physics M.C. - Section B PB - FMl -M/ 19 Force & Motion I Position and Movement M78. a ball is released from rest at a certain height above the ground. If air resistance is neglected, what is the ratio of (6) the distance travelled by the stone in the second to that travel led in the third second? � 3 B. 5 C. 5 D. 8 PartC: The following questions are designed to give supplemental exercise for this chapter. M69. A car travels with a speed of l 8 m s-1• The driver suddenly sees a girl standing at 36 m in front. If the reaction time of the driver is 0.5 s, what should be the minimum deceleration of the car in order to avoid collision with the girl? A. 3.0 m s-2 8. 4.5 m s-2 C. 6.0 m s-2 D. 9.0ms-2 M70. vim s- 1 "r t ._·---,.---... 0 f1-l -� ·� ,,. M71. -10 �----H ____________ H _____�: ,I. The figure shows the time variation of the velocity of a car travelling along a straight road, starting from rest at a c ertain point P. What is the maximum distance from the point P that the car would reach within the time shown in the figure? A. !00m B. 150m C. 200 m D. 250 m Displacement from S Two cars A andB move along the same straight road. The variations of their displacement from an oil Station Swith time are shown in the above figure. Which of the following statements is/are correct? (l) The cars travel with the same velocity. (2) At time t o , the two cars meet each other. (3) The two cars have travelled the same distance from t "" 0 to I"' t.,. A _ (2) only B. (3) only C. (1) & (2) only D. (2) & (3) only DSE Physics M.C. - Section B PB - FMl- M / 2o Force & Motion I Position and Movement M7 2 Peter walks along a straight road from point P to point Q with an average speed of2 m s-1• He then runs back from Q to P along the same road with an average speed of 4 m s-1• Which of the following statements are correct? ( 1) The resultant displacement of Peter in the whole journey is zero. (2) The average velocity of Peter in the whole journey is Om s-1• (3) The average speed of Peter in the whole journey is 3 m s-1• A. (l) & (2) only B. Cl) & (3) only C. (2) & (3) only D. (1), (2) & (3) M7 3. ln the figure shovm, one ball is released from rest at the top of a tower that is 100 m high. The other ball is released from rest at the mid-point of the tower. Which of the following quantities is the same for both balls as they full in air? (Neglect air resistance.) A. change of velocity just before reaching the ground B. acceleration during the fall C. finalvelocity justbeforereachingtheground D. time of travel in the journey 0 lOOm 0 50m tower M74. A boy wants to measure the height of building. He releases a stone at the top of the building from rest and starts to keep the time. If the stone takes 2 s to reach the mid-height of the building, which of the following statements is/are correct? Take g to be 1oms-2. (1) The height of the building is 40m. (2) The stone takes 45 to reach the bottom of the building (3) The stone reaches the bottom of the building with a speed of 4oros-1 A. (1) only B. (3) only C. (I) & (2) only D. (2) & (3) only M7 5. The graph shows the velocity of a body travelling in a straight line. What is the averagevelocity of the body during the first 3 s? A. 4m s-1 Velocity/ m s-1 C. 9m s-1 Time/s D. 12ms-1 M7 6. A car takes 20 s to travel the first 80 m, and another l Os to travel a further 70 m. What is the average speed ? A. 2.5 m s-1 B. 4.0 m s~ 1 C. 5.0 m s-1 D. 5.5 m s-1 M77. Peter throws a ball downwards at an initial velocity of5 m s- 1 from the top of a building.After3 s. the ball reaches the ground. What is the height ofthe building? A. 29m B. 44m C. 59 m D. 88m DSE Physics - Section B : M.C. FM:1 : Position and Movement PB-FMl-M/21 78. A feather is dropped downwards with an initial velocity of2 m s-1 at a height of15 m above the surface of the M oon. It is known that the acceleration due to gravity on the Moon's surface is 16% of that of the Earth. Calculate the speed of the feather when it reaches the surface of the Moon. .:A 6.85m s-1 B 7.lSms- 1 e, 8.45ms- 1 D 9.25ms-1 79. Two balls of the same mass are dropped from the top of a tall building one after the other. Air resistance is negligible. The separation between the two balls A remains constant B decreases with time. t!. increases with time, D depends on the mass ofthe two balls. 80. Two identical balls are held above the ground as shown. One ball is higher than the other ball by a separation As. Air resistance is neglig1ble, Suppose tbetwo balls are released at the same time. During the .fligb.t, $rir separation will 81. A remam cOllStant B decreases with time. C. increases with time, D increases and then decreases. A fish jumps up with a certain initial speed to leave the water surface, It reaches a maximum. height of 80 cm above the water surl'a.ce and retum.s back to the water. Treat the fish as a particle and neglect the air resistance, what is the time interval that the fish is above the water surface? (Take gto be 10 ms- 2 .) A 02, is 0.4 s c 0.8 s D L6s 82. Ball Pis thrown vertically upwards from the ground with an initial velocity of25 m s- 1• At the same time, ball Q is thrown vertically downwards with an initial vel ocity of 15 m s- 1 at the top of a building 80 m above the ground. Asswne air resistance is negligible and their motions are along the same vertical line, detennine the height that the two balls meet. Take the acceleration due to gravity to be 10 m s- 2• A. 30m B. 40m C. 50m D. 60m 83. A particle accelerates from rest with a uniform acceleration a along a straight line. It travels a distance of x in the third second and travels a distance of y in the fifth second. Find the ratio ofx toy. A 3:5 B. 5:9 C. 9: 16 D. 9:25 DSE Physics - Section B : MC. FM:1 : Position and Movement PB-FMl-M/22 84. A car··1ni.vels with a constant speed of 50 km h- 1 during a 1:fuie interval. Which of the following values CANNOT be the possible average velocity of the car in this time interval? A. 0kmh- 1 B. 25 kmh- 1 c. 50kmh- 1 D. 75 kmh-1 85. A boy throws a small ball upwards with an initial velocity of 15m s- 1 at the top ofa building. The height of the building is 30 m. If air resistance is negligible, calculate the time taken for the ball to reach the ground. A 222s B. 333 s c. 4.448 D. 5.55 s t 86. A particle moves with an initial velocity of 5 in s- 1 on a straight line under a unifonn acceleration of 2 mS- 2• What is the distance travelled by the particle in the fourth second? A 12m B. 24m C. 36m D. 48m A. ball is thrown vertically upwards with an :initial velocity of 16ms- 1 • What is the total distance travelled by the ball when it returns to the o.'¾'ii.:t(),I p..k'"itr� · . 1 /h 13m lh. !Sm C· 26m D ... 32m Part D : HKDSE examination questions 88. < HKDSE Sa mple Paper IA- 7 > 14 LL------"---* ti, 0 0.8 5.0 Patrick is driving al ong a straight horizontal road. At time t"' 0, he observes that an accident has happened. He then applies the brakes to stop his car with unifurm deceleration. The graph shows the variation of the speed of the car with time. Find the distance tni.velled by the car from time t "' 0 to 5.0 s. A 29.4m B. 40.6m C. 46.2m D. 81.2m DSE Physics - Section B : M.C. Fl\i.11 : Position and Movement PB-FMl-M/23 � , Two small ide ntical objects P and Qare released from the t op of a building 80 m above the ground . Q 1s released 1 s after P. Negle cting air resistance, what is the maximum vertical separation between P and Q i n the air ? A. Sm B. 10m C. 35m D. 45m 90. < HKDSE Practice Paper IA - 7 > A ston e falls from rest. Neglecting air resistance, th e ratio of the distance travel led by the stone in the 1st second to that travelled in the 2nd second is A. 1: 1 B. 1 :1 C. 1: 3 D. 1 :4 91. A toycar travelled due east for 10m in 5 s, then :immediately tumed north and travelled 5 m for l s. What was the average speed of the car? A. 1.9ms- 1 B. 2.2 ms- 1 C. 2.Sms- 1 D. 3.Sms-1 92. A particle i s released fromres t atX as shown. It takes time t1 to fall :fromXto Y and time tztofall fromYtoZ. IfXY: i'Z= 9: 16, :findt 1: k, N eglec t air resistance. A. 2 :3 B. 3:4 c. 4:3 D. 3:2 93. Two particles P and Q start from the same position and travel al ong th e same straight li ne. The above figure shows the velocity-time {v- t) graph for P and Q. Which of the followiog descriptions about their motion is/are oornct? {1} At t- 1 s, P changesits direction of IllOtion. (2) At t = 2 s, the separation between P and Q is 4 m. (3) Att=4 s,P and Qmeeteach other. · A. (1) only B. (2) only c. (1) & (3) on ly D. (2) & (3) only 4 3 2 1 -2 Smin ls 10min5s :x + y ''' • z .., ground '-''��"""""" / i , p t I, . DSE Physics - Section B : M.C. FMl : Position and Movement 94. PB-FMl-M/24 A particle is moving along a straight line with uniform accele ration. It truces 4 s to travel adistance of 36 m and then 2 s to travel the next 36 m. Vlhat is its acceleration? A, 2.5ms· 2 ·(3.... 3.0ms- 2 ·C.., 4.0ms- 2 p, 4.5 ms· 1 95. < HKDSE 2014 Paper IA- 9 :> A partic le is projected vertically downward with an initial speed of 2.0 m s- 1 from the rooftop of a house. The particl e reache s the ground with a spe ed of 11 m s- 1 as shown. Estimate the height of the h ouse. Neglect air resistance. A. 33m B. 6.0m C . 6.5m D. 12m 96. The figure shows the velocity-time (v-t) graph of two carsP and Q travelling along the same straight road. At t = 0, the cars are at the same position . Which ded uc tions about the cars between t = 0 and t = t2 are correct ? (1) P and Q are always travell ing in the same d:ircct:ion. (2) At, t = ti. the separation betwee n P and. -Q is at a maximum. (3) Att = t2,�ebindP. A c1) & (2) only , \3 (1) & (3) only C. (2) & (3) on ly .a (1),(2)&(3) 2.0m ,-, i �flop t D llms- 1 ! V - Q � 0 houso I/ A particl e travels at2.0 ms· 1 due e ast for 1.5 sand the n travels at 4.0m s· 1 d ue north for LO s. What is th e magnitude of its 0,verage vel ocity for the wholejourney ? A: 2.0ms· 1 B ... 2.8ms·1 '&.'" 3.0m s- 1 v'�5.0ms· 1 98. Thespeedometer of a carshown indicates the car's A.� 'ih.stantane ous sp eed. i).., 1nstantaneous velocity. (... uwerage speed of the whole journey. · l) .,_ q..,rerage velocity of the whole journey. DSE Physics • Section B : MC. FMl : Position and Movement PB-FMl-M/25 99. Which ofthefollowing statenients about the motion of any two objects is correct? , The object that takes a shorter time to complete the same path. must have greater average speed. The object that travels a greater distance in I s must have greater ave.rage velocity. The object with greater velocity must have greater acceleration. ff the two objects have the same acceleration, th ey must be moving in the same direction 100. 101 A ca. taJccs g muwtes tG uave1 along a� OFQR on a borizotttal_ � as shown. Given that OP .. PQ-2 Jan. find the � ofthe avm,ge velocity of the car m tfusJQUfflet• A. B. C. D. 30kmh- 1 36kmX 1 41 kmh- 1 St kmb -i I DSE Physics - Section B : M.C. Solution FMl : Position and Movement PB-FMl -MS/01 HXEAA's Marlcir1g Scheme is pmpamd for the markets' reference. It should not be :rega?C}ed as a set of model answers. Students and teachers who are not involved :in the marking process are advised to intcJ:pret the Marldng Scheme with care. M.C. Answers I. D 2. A 3. D 4. D 5. B 6. D 7. C 8. C 9. B 10. C 51. B 52. D 53. A 54. A 55. A 56. D 57. A 58. C 59. A 60. C ' M.C. Sohm.on !. D II. B 12. B 13. D 14. B 15. B 16. D 17. A 18. C 19. A 20. B 61. C 62. C 63. A 64. B 65. A 66. C 67. D 68. C 69. C 70. C 21. C 31. B 22. D 32. B 23. B 33. C 24. B 34. D 25. C 35. B 26. D 36. B 27. C 37. C 28. D 38. B 29. B 39. A 30. C 40. C 71. D 81. C 72. A 82. A 73. B 83. B 74. A 84. D 75. B 85. C 76. C 86. A 77. C 87. C 78. B 88. B 79. C 89. C 80. A 90. C s = ut+ ½at 2 :, (4) = {0)+ ½g(1)2 g = Smir' s = ut+ ½ gt 2 = (0)+ ½(8)(1 +4)2 = 100m 2. A FromAtoB: s = ut+ fot 2 FromOtoA: v = u+ot (100) = u {4) + f (9.81)(4) 2 (5.38) = (0) + (9.81) t 41. D 101. A 42. A 43. D 44. B 45. A 46. B 47. B 48. B 49. A 50. C 91. C 92. D 93. B 94. B 95. B 96. D 97. A 98. A 99. A 100. D u = 538 ms- 1 t = 0.548 "" 0.55 s 3. 4. 5. D ✓ ✓ ✓ D (I) (2) (3) DSEPhysics- Section B: MC. Solution FMl : Position and Movement Ullllonn velocity ⇒ acceleration a =0 PB-FMl-MS/02 Example : If a ball is projectedupwards, its velocity is zero at the highest point, but a= g ;:!: 0 Example : If a car turns roundwith constant speed, as the direction is changing , the velocity varies. s = areaofthegraph= (Z+4)x4 = 12m 2 B In vacuum, there is no air resistance, the ping-pong ball wouldfall under the acceleratio n due to gravity. v = u+at = O+gt V � I v ~ t graph is a straight line through the origin 6. D 7. 8. 9, By v 2 = u 2 + 2as 0= u 2 + 2(-a)s C :. u 2 =2as a= slope of the graph "" 6-0 = 2m s- 2 3-0 C Bys = ut + ½at 2 = (0) + ½(9.81)t 2 "" 4.9t 2 After falling for 1 s : SI = 4.9 x (1)'- = 4.9 m Afterfallingfor2s: sz= 4.9x(2) 2 = 19.6m After falling for 3s: 33= 4.9 x (3) 2 = 44.1 m U 2 CC S :. sz = 29.4m Dista nce travelled in the first second = 4.9 m Distancetravelledinthethirdsecond = 44.1 - 19.6 = 24.Sm B ✓ (I) (2) (3) Displacement increases in: 1 cm , 3cm, 6cm, 10cm, 15 cm, 21 cm; not uniformly Length ofeach section of tape represents thevelocity :. Velocity increases in unit of: 1, 2. 3, 4, 5, 6; ie. increases llllifonnly Since velocity increases unifonnly, the acceleration is constant and not increasing 12. C DSE Physics - Section B : M.C. Solution FMl : Position and Movement s = ut+lat 2 = (O)t+lat 1 2 2 slope of the graph = .!:.a 2 4-0 1 -- =-a OR 4-0 2 :. a =2ms"" 2 At t 2 = 4s 2 ,di sp lacements=4m. Bys=ut+ ½at 2 (4) = (0) + ½a(4) B Time interval for each flash = .!. = 0.5 s AtMN,averagespeed: v = 36-16 = 40cms- 1 0.5 B (1) (2) It falls with the acceleration due to gravity, thus the speed is increasing. A:fterl S, s = u r + ½ a t 1 = (0) + ,½ (9.8)(1)1= 4.9 m. PB-FM1-MS /03 Moreover, as it falls with acceleration, the distance travelled in everysecondshould be increaslllg. ✓ (3) Acceleration of 9.8 ms- 2 means in each second, there is a change in velocity of 9.8 m s- 1 A:fter2s,speed = 9.8x2 = 19.6ms- 1• 13. D At the maximum height, velocity is zero but the acceleration of the particle is still equal to the acceleration due to gravity which is pointing do'ND.wards. 14. B AE air has been evacuated, the tube is vacuum, thus there is no air resistance acting on the falliog object Coin : falls with uniform acceleration (as it falls 1.lllder gravity) Feather : falls with same uniform acceleration (as it experiences the same a cceleration due to gravity if no all" resistance) 15. B By v2=u2+2as .-. slopeofthegraph= 2a OR 4-0 = 2a 2-0 At the point when s = 3m, v2= 6m1- s- 2 By v2=ii+2as :. (6)=(0)+2a(3) :. a = lms- 2 r 16. 17. D DSE Physics - Section B : M.C. Solution FMl : Position and Movement T:imcintervalbetween2fushes = .!. =0. 2s 5 u = o.o4 = 02ms- 1 (occurattheinstantofthemidpointof4cm) 0. 2 v = 0.12 = 0. 6 ms- 1 (occurattheinstantofthemidpointofl2cm) 0. 2 From the instant of u to the instant ofv, there are only 2 time intervals, that is, 2 x 0. 2s, A ✓ X a=�=�= lms- 2 t 2x0. 2 (1) 20-10 -1 a=slope of the graph= -- = 2ms 10-0 1 s = area of the graph= 2(10+25)x20 == 350m PB-FMl-MS/04 X (2) (3) At 25 s, the displacements is 350 m. whi ch is not Om, thus it is not the starting point 18. C 19. 20. Slope of s ~ t graph represents velocity. For a particle illOVingwi:th dece leration, its velocity is decreasing. The s ~ t graph with decreasing slope represents uniform deceleration . A v _ resultant displacement =_3_ =0 _6 m 6-1 totaltime taken 2 + 3 B Displacement s = net area ofv-t graph = f (6) (60) - f (18 -6)(120) = -540m .·. The displacement is 540m in downward direction ·. Height of the cliff is 540 m 21. C ✓ ✓ (1) (2) (3) Fallitlg back to A means returning to the original position :. s = O When moving inair, the acceleration is equal to the acceleration due t o gravity gvm.ichis cOllStant Same acceleration in upward and downward motion if there is no air resistance X ;. timeforupwardmotion = timefordownwardmotion 22. 23. 24. 25. 26. 27. D DSE Physics - Section B : M.C. Solution FMl : Position and Movement Time interval between 2 dots : 1 tick = ...!:.... = 0. 02 s 50 u = O.OlS = O.lSms- 1 (occuratth einstant ofthemidpointofl. 5cm) Sx0. 02 v = 0.036 = 036ms- 1 (occurattheinstantofthemidpointof3. 6cm) 5x0. 02 From the instant ofu to the instant ofv, there are 10ticks, that is, 10 x 0. 02s. B v-u 0.36-0. 15 a=-,-= IOx0.02 1.05ms- 2 Slope ofthe v- t graph = ac celeration PB-FMl-MS /OS Before t = t 0 , accelerati on is positive and constant, v- t graph is astraight lin e that v increases from Oto v After t = t O , acceleration is zero, thus v ~ t graph a horizontal lineand velocity continues from v and remains constant B X (1) X (2) ✓ (3) C Displacement s =,,/so '- + 6� = 100 m 80+60 ➔ speed= 30+10 = 3.5ms v=�=2.5ms- 1 30+10 Distance travelled = total area of the graph between the line and th ex-axis As distattce is a scalar, the ais (-) 33. C s 120+100 v=-=--- t 30+20 :. v = 4.4ms- 1 34. D DSE Physics - Section B : M.C. Solution FMl : Position and Movement Asslop e of v - t graph= acce leration, Wh en t=Ostot=lOs, a:(+)⇒ slopeo fv~tgraph:(+) Whe nt=l0stot=20s, a:(+)⇒ slopeofv~tgraph:O (aho r izontalline) PB-FMl-MS/07 When t=20 s to t=30 s, a:(+) with larger value => slope o fv~ t graph:(+) with larger slo pe 35. B X X ✓ (!) (2) (3) At T ,, , the two cars do not havesame di sp lace ment, therefore , they do not meet each other. At T 0 , the two cars have the same positive velocity, thus they must move in the same direction. Car A travels with increasing velocity while car B travels with decreasing velo city 36. B 37. 38. 39. v = lOOxlOOO = 27_78 ms-t 3600 Byv = u+at :. {27.78) = (0) + a (3.2) :. a= 8.68ms- 2 C Assume an arbitrary value (1£-:titti) for the distance between A andB, say 10 m. TimetakenfromAtoB = � = 10s I Time taken fromB to A = � = � Averagespeed = Total distancetravelled = 10+10 = 1. 33 m 5_ 1 Total time taken 10+5 B X A. Since the slope represents the speed, a straight line indi cates a constant spee d without change. ✓ B. Since distance from P is decreasing, it is moving towards P. • c Since the speed is constant, acceleration iszero and thus no unbalanced (n et) force acting on the car. X D. Area under a distance-time graph has no physical meaning. A ✓ (!) Fr omthe graph, when s=20m, car Phas a smaller value oft. Thus, Preache s the mark with ashorter ti me t. ✓ (2) From the graph, before t= 5 s, car Q has a larger value ofs, car Pis behind car Q. Att= 5 s, car P andQmeetand car Pi s overtaking car Q. X (3) Average spe e d = distance / time In the :first 5 s, car P and car Q travel thesame distance, so they have the same average speed. 40. 41. 42. 43. 44. 45. C DSE Physics · Section B : M.C. Solution FMl : Position and Movement PB-FMl-MS/08 When the string is broken, the stone has the same initial velocity as the balloon, thus it moves upward at t = 0. So the stone first moves upward (vis positive), at the highest point, it is momentarily at rest (v =Om s-1), and then falls down (vis negative). During the whole motion of falling, the stone experiences the same acceleration due to gravity g, thus the slope ofthe graph is constant and equal to -g. D Area ofa velocity-time graph represents the displacement of the car. A ✓ ✓ D (!) (2) (3) At t = t1, v = 0, the car reaches the extreme point and is momentarily at rest, it then reverses its direction of travel After t = ti, the car reverses its direction and travels backwards. Thus the car is farthest away at t i The area from t= 0 to t= t1 represents the distance travelled in forward direction while the area from t = t1 to t= ti represents the distance travelled in backward direction. As the two areas are not equal, the car does not return to its starting point at t2. Distance travelled: d = 211: x (30) = 188.5 m Average speed=!!..= 188·5 = 12.6ms- 1 B t 15 By v2=u2+1as (60) 2 = (0) + 2 (2) s s = 900m A ✓ (!) (2) (3) Area under a v-t graph represents the displacement. At time t1, area ofP is greater, thus P tra

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