6. Note that the following question has only three choices.

Transcription

1 1. A 5.0-newton force and a 7.0-newton force act concurrently on a point. As the angle between the forces is increased from 0 to 180, the magnitude of the resultant of the two forces changes from 0.0 N to 12.0 N 12.0 N to 2.0 N 2.0 N to 12.0 N 12.0 N to 0.0 N 3. Which pair of forces acting concurrently on an object will produce the resultant of greatest magnitude? 2. Which vector diagram best represents a cart slowing down as it travels to the right on a horizontal surface? 4. Two concurrent forces have a maximum resultant of 45 Newtons and a minimum resultant of 5 Newtons. What is the magnitude of each of these forces? 0 N and 45 N 20. N and 25 N 5 N and 9 N 0 N and 50. N 5. If the force vector shown in the diagram above is resolved into two components, these two components could best be represented by which diagram below? 6. Note that the following question has only three choices. A 6.0-newton force and an 8.0-newton force act concurrently on a point. As the angle between these forces increases from 0 to 90, the magnitude of their resultant decreases remains the same increases

2 7. A constant force is exerted on a box as shown in the diagram. 11. Two perpendicular forces act on an object as shown in the diagram to the right. As the angle θ decreases to 0, the magnitude of the horizontal component of the force decreases remains the same increases 8. The diagram below represents a constant force F acting on a box located on a frictionless horizontal surface. What is the magnitude of the resultant force on the object? 17 N 7.0 N 13 N 5.0 N 12. Two students push on a sled. One pushes with a force of 30. newtons east and the other exerts a force of 40. newtons south, as shown in the topview diagram below. As the angle between the force and the horizontal increases, the acceleration of the box will decrease remain the same increase 9. A boat heads directly eastward across a river at 12 meters per second. If the current in the river is flowing at 5.0 meters per second due south, what is the magnitude of the boat's resultant velocity? 7.0 m/s 13 m/s 8.5 m/s 17 m/s Which vector best represents the resultant of these two forces? 10. A 3.0-newton force and a 4.0-newton force act concurrently on a point. In which diagram below would the orientation of these forces produce the greatest net force on the point? 13. Which combination of three concurrent forces acting on a body could not produce equilibrium? 1 N, 3 N, 5 N 3 N, 4 N, 5 N 2 N, 2 N, 2 N 4 N, 4 N, 5 N

3 14. A river flows due east at 1.5 meters per second. A motorboat leaves the north shore of the river and heads due south at 2.0 meters per second, as shown in the diagram below. 15. As shown in the diagram below, a painter climbs 7.3 meters up a vertical scaffold A to B and then walks 11.0 meters from B to C along a level platform Which vector best represents the resultant velocity of the boat relative to the riverbank? The magnitude of the painter's total displacement while moving from A to C is 3.7 m 18.3 m 13.2 m 25.6 m 16. Forces F 1 and F 2 act concurrently on point P, as shown in the diagram below. The equilibrant of F 1 and F 2 is 14 N southwest 20. N southwest 14 N southeast 20. N southeast 17. Two forces (OA and OB) act simultaneously at point O as shown on the diagram to the right. The magnitude of the resultant force is closest to 8.0 N 15 N 11 N 16 N

4 18. The diagram below shows a child pulling a 50.-kilogram friend on a sled by applying a 300.-newton force on the sled rope at an angle of 40.º with the horizontal. The vertical component of the 300.-newton force is approximately 510 N 230 N 190 N 32 N 19. In the diagram below, a force, F, is applied to the handle of a lawnmower inclined at angle to the ground. 21. A force of 100. Newtons is applied to an object at an angle of 30º from the horizontal as shown in the diagram below. What is the magnitude of the vertical component of this force? The magnitude of the horizontal component of force F depends on the magnitude of force F, only the measure of angle, only both the magnitude of force F and the measure of angle neither the magnitude of force F nor the measure of angle 0 N 86.7 N 50.0 N 100. N 22. The diagram below shows a 10.0-kilogram mass held at rest on a frictionless 30.0 incline by force F. 20. In the diagram below, a block rests on a ramp, making angle Θ with the horizontal. If angle Θ is increased, what will occur? The block's mass will decrease. The block's weight will increase. The block's component of weight parallel to the ramp will decrease. The block's component of weight parallel to the ramp will increase. What is the approximate magnitude of force F? 9.81 N 85.0 N 49.1 N 98.1 N

5 23. The diagram below shows a block on a horizontal frictionless surface. A newton force acts on the block at an angle of 30. above the horizontal. 28. In the diagram below, the weight of a box on a plane inclined at 30.º is represented by the vector W. What is the magnitude of force F if it establishes equilibrium? 50.0 N 100. N 86.6 N 187 N 24. Two students are pushing a car. What should be the angle of each student s arms with respect to the flat ground to maximize the horizontal component of the force? 0º 45º 30º 90º 25. Into how many possible components can a single force be resolved? an unlimited number two components three components four components at right angles to each other 26. A resultant force of 10. Newtons is made up of two component forces acting at right angles to each other. If the magnitude of one of the components is 6.0 Newtons, the magnitude of the other component must be 16 N 6.0 N 8.0 N 4 N What is the magnitude of the component of the weight (W) that acts parallel to the incline? W 0.87 W 0.50 W 1.5 W 29. A block is at rest on an inclined plane as shown in the diagram at the right. As angle θ is increased, the component of the block's weight parallel to the plane decreases remains the same increases 30. The diagram below shows a person exerting a 300.-newton force on the handle of a shovel that makes an angle of 60.º with the horizontal ground. 27. A lawnmower is pushed with a constant force of F, as shown in the diagram below: The component of the 300.-newton force that acts perpendicular to the ground is approximately 150. N 300. N 260. N 350. N As angle θ between the lawnmower handle and the horizontal increases, the horizontal component of F decreases remains the same increases

6 31. A 100.-newton force acts on point P, as shown in the diagram below. 35. A 5.0-newton force could have perpendicular components of 1.0 N and 4.0 N 3.0 N and 4.0 N 2.0 N and 3.0 N 5.0 N and 5.0 N 36. The mass of a physics textbook is closest to 10 3 kg 10 0 kg 10 1 kg 10-2 kg The magnitude of the vertical component of this force is approximately 30. N 71 N 50. N 87 N 37. What is the displacement of the mass hanger (H) shown in the diagram after a 0.20-kilogram mass is loaded on it? [Assume the hanger is at rest in both positions.] 32. The diagram at the right represents a force acting at point P. Which pair of concurrent forces would produce equilibrium when added to the force acting at point P? 33. As the angle between a force and level ground decreases from 60º to 30º, the vertical component of the force decreases remains the same increases 34. The handle of a lawn roller is held at 45º from the horizontal. A force, F, of 28.0 Newtons is applied to the handle as the roller is pushed across a level lawn, as shown in the diagram below cm cm cm cm 38. The height of a doorknob above the floor is closest to 1 centimeter 1 millimeter 1 meter 1 kilometer 39. The area of a page in a test booklet is closest to 0.6 cm 2 60 cm 2 6 cm cm An egg is dropped from a third-story window. The distance the egg falls from the window to the ground is closest to 10 0 m 10 2 m 10 1 m 10 3 m 41. Which measurement of an average classroom door is closest to 1 meter? thickness height width surface area What is the magnitude of the force moving the roller forward? 7.00 N 19.8 N 14.0 N 39.0 N 42. The mass of a high school football player is approximately 10 0 kg 10 2 kg 10 1 kg 10 3 kg 43. What is the approximate mass of an automobile? 10 1 kg 10 3 kg 10 2 kg 10 6 kg

7 44. What is the approximate mass of a chicken egg? 1 10 l kg 1 10 l kg kg kg 45. Which measurement of an average classroom door is closest to 1 meter? thickness height width surface area 46. Which is the most likely mass of a high school student? 1 kg 60 kg 5 kg 250 kg 47. A reasonable height for a chalk tray above the floor is closest to 1 cm 100 cm 10 cm 1,000 cm 48. The height of an average adult is approximately 1.75 cm mm m km 49. The length of a high school physics classroom is probably closest to 10 2 m 10 1 m 10 1 m 10 4 m 50. The thickness of a pencil is closest to 1 mm 1 m 1 cm 1 km 51. The weight of an apple is closest to 10 2 N 10 2 N 10 0 N 10 4 N 52. The diagram below represents two forces acting concurrently on an object. The magnitude of the resultant force is closest to 20. N 45. N 40. N 60. N 53. As the angle between two concurrent forces of 5.0 Newtons and 7.0 Newtons increases from 0º to 180º, the magnitude of their resultant changes from 0 N to 35 N 12 N to 2.0 N 2.0 N to 12 N 12 N to 0 N 54. If a man walks 17 meters east then 17 meters south, the magnitude of the man's displacement is 17 m 30. m 24 m 34 m 55. The resultant of two concurrent forces is minimum when the angle between them is 0º 90º 45º 180º 56. What is the magnitude of the vector sum of the two concurrent forces represented in the diagram to the right? 2.5 Newtons 3.0 Newtons 3.5 Newtons 4.0 Newtons 57. A force of 3 Newtons and a force of 5 Newtons act concurrently to produce a resultant of 8 Newtons. The angle between the forces must be 0º 90º 60º 180º 58. If two 10.-newton concurrent forces have a resultant of zero, than the angle between the forces must be The resultant of two forces acting on the same point at the same time will be greatest when the angle between the forces is 0º 90º 45º 180º 60. The diagram at the right represents two concurrent forces acting on a point. Which vector best represents their resultant?

8 61. What is the approximate length of a baseball bat? 10 1 m 10 1 m 10 0 m 10 2 m 62. An object is displaced 3 meters to the west and then 4 meters to the south. Which vector shown below best represents the resultant displacement of the block? 64. As the angle between two concurrent forces is increased from 10º to 75º, the magnitude of the resultant force decreases remains the same increases 65. An object is displaced 12 meters to the right and then 16 meters upward. The magnitude of the resultant displacement is 1.3 meters 28 meters 20 meters 4.0 meters 66. As the angle between two concurrent forces increases from 45º to 90º, the magnitude of their resultant decreases remains the same increases 67. Two forces of 100 Newtons and 25 Newtons act concurrently on an object. These two forces could have a resultant force of 0 N 100 N 50 N 150 N 68. Which vector below best represents the resultant of the two vectors shown to the right? 63. Forces A and B have a resultant R. Force A and resultant R are shown in the diagram below. Which vector below best represents force B? 69. A girl attempts to swim directly across a stream 15 meters wide. When she reaches the other side, she is 15 meters downstream. The magnitude of her displacement is closest to 30 m 17 m 21 m 15 m

9 Answer Key Vectors [Jun 21, 2010]

10 Answer Key Vectors [Jun 21, 2010]