Physics. Practice Questions IEB

Transcription

1 Physics Practice Questions IEB

2 Instructions Individual, eam-style questions The questions contained in this booklet match the style of questions that are typically asked in eams. This booklet is not however, a practice eam. Elevate s research with top students identified that top students do more practice questions than anyone else. They begin the process of testing their knowledge early in the year. Therefore, we have provided eam-format questions that are sorted by topic so that you can answer them as you learn the information, rather than waiting until the very end of the year to complete eams. Comments, questions? Let us know if you need any further advice by visiting You can comment on any of our material, or head to the FAQ section and ask us a question. Also, you can find us on social media so you can stay up to date on any brand new tips we release throughout the year. Other information Every effort has been made to ensure the accuracy of the information epressed in this booklet, but no warranty or fitness is implied. If you d like to provide any feedback on this booklet, let us know at admin@elevateeducation.com. Finally, no part of this publication may be reproduced, stored in a retrieval system, or transmitted by any means without prior written consent of the publisher. 2

3 Multiple Choice questions 1. An object is thrown vertically upwards, reaches its maimum height and allowed to return to its original point of projection. Ignoring the effects of friction, the acceleration of the object during its motion is.. A constant in magnitude and always downwards. B constant in magnitude, initially upwards and then downwards. C initially upwards and maimum in magnitude and then downwards and minimum in magnitude D constant in magnitude and always upwards Answer: A 2.A body moving at a constant velocity has kinetic energy E, as well as momentum p. If the velocity of the body is doubled, which one of the following correctly gives the magnitudes of both kinetic energy and momentum? Kinetic Energy Momentum A 2E 2p B 4E 4p C 4E 2p D 2E 4p 3

4 3. The gradient of the graph below represents. Change in momentum (kgm/s) 40 A. energy B. work C. displacement 0 D. resultant force Time (s) Answer: D 4. Which one of the following represents the charge on X and Y respectively? Point charge X Point charge Y A Negative Negative B Positive Positive C Positive Negative D negative Positive 4

5 5. Tim is a passenger seated in an aeroplane which is accelerating along the runway before take-off. Which free body diagram correctly shows the forces that act on Tim as the plane accelerates to the right, along the runway. A. force of seat on Tim B. force of seat on Tim Tim s inertia Force of back of seat on Tim Tim s inertia Tim s weight weight C. D. Force of seat on Tim Tim s Force of seat on Tim Force of back of seat on Tim Tim s weight Force of Tim on seat Force of back of seat on Tim Tim s weight 5

6 5. A child throws a rubber ball vertically downwards from a balcony onto the road below. The following velocity vs. time graph was obtained: 15 v (m.s -1 ) 5 0 t = 0.8s t (s) -12 From what height was the cricket ball thrown? A. 4 m B. 8 m C. 12,5 m D. 16 m Answer: A 6. Consider a current carrying conductor placed in a uniform magnetic field as shown. The conductor will eperience a force: A Into the page B Out of the page C Upwards D Downwards Answer: D 6

7 7. Two rigid rods, XZ and YZ, are fied to a vertical wall at X and Y. A load of weight W is hung from Z and remains stationary. X Y Which diagram shows the forces acting at point Z? Answer: A 7

8 8. An investigation is conducted to observe the interference pattern produced when red light is shone through a diffraction grating and allowed to form a fringe pattern on a screen 1 m away. Which of the following changes would produce a pattern with smaller spaces between consecutive antinodes? A. Move the screen further from the grating B. Use a diffraction grating on which the slits are closer together C. Use blue light instead of red D. move the light source closer to the grating 9. This graph shows the current generated when a generator coil is rotated in a magnetic field. S + Current I (A) 0 - time (s) The position of the rotating coil corresponding to point S on the graph above is: A. Moving at 45 to the magnetic field B. Moving perpendicular to the magnetic field C. Moving parallel to the magnetic field D. Not moving in the magnetic field Answer: B 8

9 10.Consider the circuit represented below: 6V V 2Ω A 3Ω Which set of answers best describes the changes in the ammeter and voltmeter readings when the bulb in the circuit blows? (ignore internal resistance) ammeter voltmeter A increase Increase B Decrease No change C increase No change D decrease decrease Answer: D 11. Consider the following current carrying conductor placed in a magnetic field. The conductor is observed to move upwards as a result of the interaction between the magnetic field produced by the conductor and the permanent magnet. N S State which is appropriate for the conventional current within the conductor? A Electrons flow out of the page. B Electrons flow into the page. C Current is out of the page. D Current is into the page. 9

10 12. A bo with a weight of 20 N is on a horizontal surface. A force of magnitude 16 N is applied to the bo as shown, at an angle of 30 degrees to the horizontal. The magnitude of the normal force, applied by the surface on the bo, in this situation, is closest to which of these values? A. 4 N B. 6 N C. 8 N D. 12 N Answer: D 10

11 13. A bo of mass M is on the floor of a lift, with a bo of mass m on top of it. The lift may or may not be accelerating. In what situation is the force that the lower bo eerts on the upper bo the same magnitude as the force that the upper bo eerts on the lower bo? A. Never B. Only when m = M C. Only when the lift is not accelerating D. In all situations Answer: D 11

12 14. The picture above shows two cases involving a bo with a weight of 20 N, which is on a frictionless horizontal surface. In case 1, the bo is connected by a string over a pulley, to a second bo, with a weight of 8 N. In case 2, the bo is being pulled by someone eerting an 8 N force on the end of a string. Which of the following statements concerning the acceleration of the 20 N bo is true? A. Acceleration is greatest in case 1 B. Acceleration is greatest in case 2 C. Acceleration is equal in both cases D. The 20 N bo will not accelerate in either case Answer: B 12

13 15. You are moving with a motion that is described in the acceleration vs time graph below a (m.s -2 ) t (s) What will be your change in velocity over the 8 s shown? A. 10 m.s -1 B. 15 m.s 1 C. 30 m.s -1 D. Insufficient information provided Answer: A 16. Two balls P and Q are thrown into the air simultaneously from the same height above the ground. P is thrown upwards and Q downwards with the same initial speed. Which of the following is true of both balls just before they reach the ground? (Neglect any air resistance. Take downwards as the positive direction). Velocity Acceleration A The same The same B P has a greater velocity than Q P has a negative acceleration; Q has a positive acceleration C P has a greater velocity than The same Q D The same P has a negative acceleration; Q has a positive acceleration. Answer: A 13

14 17. Net force is a measure of : A. change in energy B. rate of change in energy C. rate of change in momentum D. change in momentum 18. If the momentum of an object, of constant mass, is doubled, then its kinetic energy will be A. halved B. doubled C. three times greater D. four times greater Answer: D 19. An electron moves into a region of uniform magnetic flu density between the poles of a magnet as shown in the diagram. electron S N The deflection of the electron will be A towards the pole marked S B towards the pole marked N C perpendicular to the plane of the paper towards you D perpendicular to the plane of the paper away from you Answer: D 14

15 20. Which of the following is true concerning Newton s law of universal gravitation? A. The force between masses can be attractive or repulsive B. The magnitude of the force between masses is directly proportional to the sum of the masses C. The magnitude of the force between the masses is inversely proportional to the square of the distance between the mass centres D. G = 6, N.m 2.kg -2 only on earth 21.Consider a bar magnet inserted into a coil as shown in the diagram below: The current in the coil and the polarity of the coil closest to the observer, as viewed from the left, would be: A Clock wise ; North B Anti-clockwise ; South C Clock wise ; South D Anti-clockwise ; North Answer: D 22. In the sketch below, a conductor carrying current, I, is placed in a magnetic field. Which one of the following best describes the force eperienced by the conductor? A. Parallel to the direction of the magnetic field B. Opposite to the direction of the magnetic field C. Into the page perpendicular to the direction of the magnetic field D. Out of the page perpendicular to the direction of the magnetic field. Answer: D 15

16 23. In the graph shown, the solid curve shows how the emf produced by a simple generator varies with time. The dashed curve is the output from the same generator after a modification has been made to the generator. Which modification was made to produce the result shown? A B C D The area of the coil was doubled. A split-ring commutator was added. The speed of rotation of the coil was doubled. The number of turns in the coil was quadrupled. 24.A mass is suspended from a roof by cable X. It is then attached to a vertical wall by a second cable Y, as shown in the diagram. Which diagram correctly shows all the forces acting on the mass? 16

17 25. A soccer ball is dropped from a height h above the ground and strikes the ground at a speed v. Ignoring air friction, from what height must the ball be dropped to strike the ground at double the speed? A. 2 h B. 3 h C. 4 h D. 5 h 26. On its own, a tow truck has a maimum acceleration of 3 m.s -2. What would its maimum acceleration be while towing a vehicle twice its own mass? A. 2,5 m.s -2 B. 2,0 m.s -2 C. 1,5 m.s -2 D. 1,0 m.s -2 Answer: D 27. The instant a steel ball M is dropped from rest from a certain height, another steel ball N is projected vertically upward from ground level. The maimum height that N reaches is the same height from which M is dropped. M does not bounce when it hits the ground. M height N Consider the motion of N only for its rise upward. Which one of the following pairs of statements, regarding the speed and acceleration of the balls, is true when they at the same height? Air resistance is negligible. 17

18 Speed Acceleration A. Speed of M < Speed of N The directions of the acceleration of M and N are both downward B. Speed of M = Speed of N The directions of the acceleration of M and N are both downward C. Speed of M > Speed of N The direction of the acceleration of M is downward and that of N is upward D. Speed of M = Speed of N The direction of the acceleration of M is downward and that of N is upward 28. Answer: B X Z uniform magnetic field Y The diagram shows a square coil with its plane parallel to a uniform magnetic field. Which one of the following would induce an emf in the coil? A B C D movement of the coil slightly to the left movement of the coil slightly downwards rotation of the coil about an ais through XY rotation of the coil about an ais perpendicular to the plane of the coil through Z 29. A bo is pulled across a horizontal floor by a force of 60 N. There is a constant frictional force of 40 N. The bo moves a distance of 6,0 m. What is the work done against friction and the change in the kinetic energy of the bo? 18

19 Work done against friction (J) Change in kinetic energy (J) A B C D Answer: A 30. The diagram shows a wire carrying a current, I, in the plane of the paper and in the south direction. A magnetic field is applied perpendicularly to the paper and acts into the paper. What is the direction of the force acting on the wire? N I W S E A B C D north south east west 31. A 2,0 kg mass travelling at 3,0 m.s -1 on a frictionless surface collides head-on with a stationary 1,0 kg mass. The masses stick together on impact. How much kinetic energy is lost on impact? A. Zero B. 3 J C. 2,4 J 19

20 D. 2 J Answer: B 32. Two small, identical metal spheres, each carrying equal charges +Q, are brought into contact and then separated. The charge on each sphere will now be : A. Zero B. ½ Q C. Q D. 2 Q 33. Cars are designed so that sections collapse when there is a collision. These sections are known as crumple zones. The diagram shows a car colliding with a wall. Which statements help to eplain why crumple zones tend to reduce injuries in the event of a collision? 1 The deceleration of the car is reduced. 2 The time taken for the car to come to rest is reduced. 3 The rate of change of momentum is reduced. 4 The loss in kinetic energy of the car is reduced. A. B. C. D. 1, 2 and 3 only 1 and 3 only are 2 and 4 only are 4 only is correct are correct correct correct Answer: B 34. Two identical conducting spheres X and Y carry charges of +3, C and -6, C respectively. The spheres are allowed to touch. During touching, sphere X gains A. 1 electron B. 2 electrons C. 3 electrons D. 6 electrons 20

21 35. The acceleration due to gravity on the earth is g. What is the acceleration due to gravity on a planet which has double the mass of the earth and half the radius of the earth? A. 8 g B. 4 g C. 2 g D. ½ g Answer: A 36. Fabio conducts an eperiment to investigate the effect of a magnet on a solenoid. As shown in the diagram, he pushes the magnet towards the solenoid and the meter connected to it shows a deflection to the left. What is the deflection when the magnet is pulled away from the solenoid at the same speed? C. To the left with smaller deflection D. To the left with the same deflection A. To the right with the same deflection B. To the right with a smaller deflection 37. In the diagram below, a conductor placed between two magnets is carrying current out of the page. Answer: A The direction of the force eerted on the conductor is towards: A. I B. II C. III D. IV Answer: A 21

22 38. Consider the following graph produced by the clock-wise rotation of a coil within a magnetic field. What is true of the coil and of its position during the rotation, when the voltage at (iii) is produced? A The coil is attached to a split-ring and the plane of the coil is at 90 0 to the field. B The coil is attached to a split-ring and the plane of the coil is in the plane of the field. C The coil is attached to a slip-ring and the plane of the coil is at 90 0 to the field. D The coil is attached to a slip-ring and the plane of the coil is in the plane of the field. Answer: D 22