VECTORS REVIEW NAME:

Transcription

1 VECTORS REVIEW NAME: 1. The vector diagram below represents two forces, F 1 and F 2 simultaneously acting on an object. Which vector best represents the resultant of the two forces? 2. A child walks 5.0 meters north, then 4.0 meters east, and finally 2.0 meters south. What is the magnitude of the resultant displacement of the child after the entire walk? 1.0 m 3.0 m 5.0 m 11.0 m 3. As the angle between two concurrent forces decreases, the magnitude of the force required to produce equilibrium increases remains the same decreases 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. What is the total displacement of a student who walks 3 blocks east, 2 blocks north, 1 block west, and then 2 blocks south? 0 2 blocks west 2 blocks east 8 blocks 6. The resultant of two concurrent forces is minimum when the angle between them is 0º 90º 45º 180º 7. The diagram below shows a resultant vector, R. Which diagram best represents a pair of component vectors, A and B, that would combine to form resultant vector R?

2 8. Forces A and B have a resultant R. Force A and resultant R are represented in the diagram below. Which vector best represents force B? 11. The speed of a car is decreased uniformly from 30. meters per second to 10. meters per second in 4.0 seconds. The magnitude of the car s acceleration is 5.0 m/s m/s m/s m/s 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 9. A plane flies 400. kilometers south and then 300. kilometers east. The magnitude of the displacement is 100. km 700. km 500. km 1,200. km 10. A 5-newton force directed east and a 5-newton force directed north act concurrently on a point. The resultant of the two forces is 5 N northeast 7 N northeast 10 N southwest 7 N southwest 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 13. A man walks 40 meters north, then 70 meters east, and then 40 meters south. What is his displacement from the starting point? 150 meters east 70 meters east 150 meters west 70 meters west 14. A car travels 12 kilometers due north and then 8 kilometers due west going from town A to town B. What is the magnitude of the displacement of a helicopter that flies in a straight line from town A to town B? 20. km 10. km 14 km 4 km 15. 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

3 16. A force vector was resolved into two perpendicular components, F 1 and F 2, as shown in the diagram below. 18. A ball is fired with a velocity of 12 meters per second from a cannon pointing north, while the cannon is moving eastward at a velocity of 24 meters per second. Which vector best represents the resultant velocity of the ball as it leaves the cannon? Which vector best represents the original force? 19. 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 20. Two perpendicular forces act on an object as shown in the diagram to the right. What is the magnitude of the resultant force on the object? 5.0 N 13 N 17 N 7.0 N 17. Velocity is to speed as displacement is to distance momentum time acceleration 21. As the angle between two concurrent forces increases from 45º to 90º, the magnitude of their resultant decreases remains the same increases

4 22. Which vector best represents the resultant of forces F 1 and F 2 acting concurrently on point P as shown in the diagram to the right? 23. Two concurrent forces of 40 Newtons and X Newtons have a resultant of 100 Newtons. Force X could be 20 Newtons 80 Newtons 40 Newtons 150 Newtons 24. As the angle between two concurrent forces is increased from 10º to 75º, the magnitude of the resultant force decreases remains the same increases 25. Forces A and B have a resultant R. Force A and resultant R are shown in the diagram below. 27. 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 28. Into how many possible components can a single force be resolved? two components an unlimited number three components four components at right angles to each other 29. 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 30. 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? Which vector below best represents force B? 0 N 86.7 N 50.0 N 100. N 31. Distance is to displacement as force is to weight velocity is to acceleration impulse is to momentum speed is to velocity 26. Which is a scalar quantity? distance displacement force acceleration

5 32. 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 33. 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. What is the magnitude of the force moving the roller forward? 7.00 N 19.8 N 14.0 N 39.0 N

6 34. The vector below represents the resultant of two forces acting concurrently on an object at point P. Which pair of vectors best represents two concurrent forces that combine to produce this resultant force vector?

7 Answer Key VECTOR WORKSHEET [Oct 24, 2011]