Physics 12 Final Exam Review Booklet # 1

Transcription

1 Physics 12 Final Exam Review Booklet # 1 1. Which is true of two vectors whose sum is zero? (C) 2. Which graph represents an object moving to the left at a constant speed? (C) 3. Which graph represents an object moving to the right and slowing down? (A) 4. Which velocity-time graph matches the displacement-time graph shown? (C)

2 5. The velocity of two objects is represented on the graph below. Which is true at point X? (A) Both objects have the same acceleration. (B) Both objects have the same displacement. (C) Object 2 has a greater acceleration than object 1. (D) Object 2 has a greater displacement than object How far does an object travel if it starts from rest and accelerates at 2.35 m/s 2 for 2.20 s? (A) 2.59 m (B) 5.17 m (C) 5.69 m (D) 11.4 m 7. How long does it take a car to accelerate from 20.0 m/s to 60.0 m/s at a rate of 8.5 m/s 2? (A) 0.11 s (B) 0.21 s (C) 4.7 s (D) 9.4 s 8. An object is thrown downwards from the top of a tall bridge with an initial velocity of 12 m/s. What is the speed of the object when it has fallen 9.5 m? (A) 12 m/s (B) 14 m/s (C) 16 m/s (D) 18 m/s 9. Balloon A is moving upwards at 4.8 m/s and balloon B is moving upwards at 1.2 m/s. What is the velocity of balloon A relative to balloon B? (B) 10. What is the reaction force when a book rests on a table? (A) force of book on table (C) force of table on book (B) force of ground on table (D) force of table on ground 11. Which is a measure of an object s resistance to changes in its motion? (A) acceleration (C) force (B) components (D) inertia

3 12. A box of mass 5.00 kg undergoes an acceleration of 3.10 m/s 2. What is the net force acting on the box? (A) N (B) 1.61 N (C) 15.5 N (D) 152 N 13. A kg puck is fired across the ice with an initial velocity of 18.0 m/s. If it takes 9.00 s to come to a complete stop, what is the magnitude of the net force? (A) N (B) N (C) 2.00 N (D) 4.00 N 14. An object at rest on a table experiences a normal force of 12 N (up). If the maximum static frictional force is 8.0 N, what is the coefficient of static friction between the object and the table? (A) 0.67 (B) 0.96 (C) 8.0 (D) A force of N is applied to an object at an angle of 20.0o above the horizontal as shown. What is the vertical component of this force? (A) N (C) 85.5 N (B) N (D) 235 N 16. A hanging mass, m, is attached to a stationary mass of 10.0 kg on a horizontal table. If the coefficient of static friction between the table and the stationary mass is 0.150, what is the maximum hanging mass that will keep the system at rest? (A) 1.02 kg (B) 1.50 kg (C) 10.0 kg (D) 66.7 kg 17. Which of Newton s laws best explains how a magician can pull a tablecloth from underneath dishes? (A) action-reaction (C) law of inertia (B) F = ma (D) universal law of gravitation

4 18. How will the magnitude of the gravitational force, F, between two objects change if one of the masses is doubled and the radius is halved? (D) 19. Which quantity is defined as the change in an object s momentum? (A) gravity (B) impulse (C) inertia (D) linear momentum 20. A kg canon fires a 20.0 kg ball at a velocity of 45 m/s (E). What is the recoil velocity of the canon? (A) 0.11 m/s (E) (C) 9.0 m/s (E) (B) 0.11 m/s (W) (D) 9.0 m/s (W) 21. A student exerts a horizontal force of N on his friend s chair to move her a distance of 2.0 m across the floor. How much work is done by the student? (A) 0 J (B) 4.0 x 10 1 J (C) 2.5 x 10 2 J (D) 1.0 x 10 3 J 22. What is the kinetic energy of a 3.0 kg ball that is moving at 2.0 m/s? (A) 3.0 J (B) 6.0 J (C) 12 J (D) 18 J 23. Bill's snowmobile is half as powerful as Bonnie's. Both are used to haul identical sled loads of wood across a pond. Which statement is correct? (A) Bill's snowmobile will do half as much work as Bonnie s. (B) Bill's snowmobile will do the same work as Bonnie s. (C) Bill's snowmobile will take twice as long to finish the job as Bonnie s. (D) Bill's snowmobile will take the same time to finish the job as Bonnie s. 24. A wheel and axle system is estimated to be 85.0 % efficient. How much work needs to be done on the system if the wheel and axle is to do 125 J of work? (A) 40.0 J (B) 106 J (C) 125 J (D) 147 J

5 25. Which represents the rate of work done? (A) efficiency (B) force (C) power (D) work 26. The picture below shows two identical blocks A and B, with mass, m, resting at the top of two hills. If the blocks slid down the hills, how would their speeds compare at the halfway point on each hill? Neglect friction. (A) speed of B is 2 times greater than the speed of A (B) speed of B is less than 2 times greater than the speed of A (C) speed of B is more than 2 times greater than the speed of A (D) speed of B is the same as the speed of A 27. A 2.00 kg cat is on a table 1.00 m above the floor. It jumps up on a shelf 2.00 m above the table. What is the gravitational potential energy of the cat with respect to the floor? (A) 19.6 J (B) 39.2 J (C) 58.8 J (D) 78.4 J 28. A spring-loaded plunger is used to launch a 1.0 kg car at 4.0 m/s along a frictionless track. The cart goes up a hill to some maximum height h. Which describes, in order, the energy transformations that occur? (Assume no friction) (A) elastic potential gravitational potential kinetic (B) elastic potential kinetic gravitational potential (C) gravitational potential kinetic elastic potential (D) kinetic elastic potential gravitational potential 29. A spring having a spring constant of 180 N/m is stretched 0.51 m from its equilibrium position. How much elastic potential energy does the spring possess? (A) J (B) 23 J (C) 46 J (D) 94 J

6 30) A 2.0 kg block and a 5.0 kg block are connected by a rope over a frictionless pulley as shown. Calculate the magnitude of the acceleration of the system of blocks. (A) 3.5 m/s 2 (B) 4.2 m/s 2 (C) 4.8 m/s 2 (D) 5.2 m/s 2 31) Use the information from 30) to calculate the magnitude of the tension in the connecting rope. (A) 43 N (B) 33 N (C) 28 N (D) 24 N 32) A changing force applied to an object is described by the F vs. d graph below. What is the work done by this force as it moves the object from 0.40 to 0.60 m? A J B. 2.0 J C. 3.2 J D. 20 J 33) Joe climbs a small hill from an elevation of 250 m to an elevation of 490 m. In doing so he expends 2.8 X 10 5 J. Joe s mass is 75 kg. What is his climbing efficiency? A B C D ) A 0.25 kg ball strikes the wall at 5.7 m s and rebounds with the same speed and angle to the wall as shown. The ball s contact time was 0.22 s. What was the magnitude of the impulse on this ball? A N s B. 1.2 N s C. 2.6 N s D. 7.4 N s

7 35) A 7.3 X 10 3 kg space vehicle and its empty 6.8 X 10 2 kg booster unit are moving together through space at 370 m s. An explosion is used to separate the two, which causes an increase in the speed of the space vehicle. The explosion lasts 2.2 s and exerts an impulse of 4.1 X 105 N s on both the space vehicle and the booster unit. What is the speed of the space vehicle after the separation? A. 400 m/s B. 430 m/s C. 480 m/s D. 490 m/s 36) A 0.50 kg puck moving at 2.0 m s collides obliquely with a stationary 0.30 kg puck. After the collision the 0.30 kg puck moves as shown. What is the speed of the 0.50 kg puck after the collision? A. 1.0 m/s B. 1.3m/s C. 1.8 m/s D. 2.2 m/s 37) Three horizontal forces are acting at the same point on a puck lying on a level frictionless table. The puck is in translational equilibrium. Two of these forces are: F1 = 10.2 N, east F2 = 15.4 N, 30 E of N What is the magnitude of the third force? A. 5.2 N B N C N D N 38) Two cables support a vertical tower. The tension in each cable is shown. What is the angle θ? A. 25 B. 28 C. 62 D. 65

8 39) If the load on the uniform beam shown below is moved to the right, how do the tension force FT in the cable and the horizontal force Fx that the hinge exerts on the beam change? (D) 40) A uniform 3.0 m long beam is supported by a cable as shown. The tension in the cable is 530 N. What is the mass of the beam? A. 33 kg B. 43 kg C. 65 kg D. 86 kg 41) A driver in a car of mass 1200 kg travelling over a circular hill of radius 35 m experienced an apparent weight of 60% his normal weight F N = (0.60 Fg). What was his speed at the top of this hill? A. 12 m/s B. 14 m/s C. 19 m/s D. 23 m/s 42) A satellite is placed in an orbit at a distance R from the centre of the earth. It is then moved to a new orbit of distance 2R from the earth s centre. Which of the following is the correct ratio of the gravitational force in the new orbit to that of the old orbit? (A)

9 43) An explorer spacecraft is descending towards Mars using a rocket engine for braking. The spacecraft has Ep = 2.8 x J and Ek = 3.0 x 10 9 J at its initial position. Some time later the spacecraft has Ep = 3.4 x J and Ek =1.0 x 10 9 J. How much work did the rocket engine do in braking the spacecraft? A. 2.0 x 10 9 J B. 4.0 x 10 9 J C. 6.0 x 10 9 J D. 8.0 x 10 9 J 44) Three point charges are arranged as shown below. What are the magnitude and direction of the electric force on the 15 μc charge due to the other two point charges? (A) 45) A small test charge is moved to several different locations near a larger fixed charge as shown. Which change in position of the smaller charge would require the most work? A. W B. X C. Y D. Z

10 46) A proton initially held at rest 2.0 m away from a fixed 25 μc charge is released. The proton accelerates to the right as shown. What is the speed of the proton when it is 6.0 m away from the 25 μc charge? A. 2.7 x 10 6 m/s B. 3.3 x 10 6 m/s C. 3.8 x 10 6 m/s D. 4.6 x 10 6 m/s 47) A 12.0 V power supply is connected to 4 resistors as shown. What is the potential difference, V 4, across the 30.0 Ω resistor? A V B V C V D V 48) An electric motor is being supplied with 500 W of power at 120 V. The resistance of the motor is 8.0 Ω. What current is being supplied to the motor? A. 4.2 A B. 7.9 A C. 15 A D. 63 A 49) A proton travelling at a certain speed follows a circular path of radius 0.24 m while in a magnetic field. An alpha particle with twice the charge and four times the mass of the proton is travelling at the same speed inside the same magnetic field. (Both particles are travelling perpendicular to the field.) What is the radius of the alpha particle s path? A m B m C m D m 50) The back emf being produced by an electric motor is increasing. The applied voltage is constant. Which of the following is correct? A. The current through the motor is constant. B. The current through the motor is increasing. C. The current through the motor is decreasing. D. The current through the motor is increasing then decreasing.

11 51) A conducting rod is placed on a U-shaped metal conductor containing a 9.0 Ω resistor. The rod is moved to the right at a constant speed of 6.2 m s through a 0.33 T magnetic field as shown. What are the magnitude and direction of the current induced in the rod? (A) 52) Due to the presence of a changing magnetic field a current is flowing in the single circular loop of conducting wire as shown below. Which of the following correctly describes the magnetic field? A. directed to the left and increasing B. directed to the right and increasing C. directed into the page and increasing D. directed out of the page and increasing 53) A proton travelling at 2.0 x 10 6 m s enters a 0.43 T magnetic field. Which of the paths shown in the diagram will the proton follow? (Diagram is not to scale.) A. P1, radius = 2.6 x 10 5 m B. P2, radius = 2.6 x 10 5 m C. P3, radius = m D. P4, radius = m

12 54) A conductor is initially at rest in a magnetic field. In which direction should the conductor be moved so that its top end becomes positively charged? A. 1 B. 2 C. 3 D. 4 55) A 55-turn circular coil of wire of radius 0.15 m is placed in a 0.76 T magnetic field as shown. The magnetic field changes to 0.34 T in the opposite direction in a time of 0.25 s. What is the average induced emf in the coil during the change in magnetic field? A. 6.5 V B. 14 V C. 17 V D. 36 V 56) Two solenoids are placed close together as shown. As the switch is closed, what is the direction of the current through the ammeter, and what is the direction of the induced magnetic field inside the second solenoid? (C)