1. (P2.1A) The picture below shows a ball rolling along a table at 1 second time intervals. What is the object s average velocity after 6 seconds?

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1 PHYSICS FINAL EXAM REVIEW FIRST SEMESTER (01/2017) UNIT 1 Motion P2.1 A Calculate the average speed of an object using the change of position and elapsed time. P2.1B Represent the velocities for linear and circular motion using motion diagrams (arrows on strobe pictures). P2.1C Create line graphs using measured values of position and elapsed time. P2.1D Describe and analyze the motion that a position-time graph represents, given the graph. P2.1g Solve problems involving average speed and constant acceleration in one dimension. P2.2A Distinguish between the variables of distance, displacement, speed, velocity, and acceleration. P2.2B Use the change of speed and elapsed time to calculate the average acceleration for linear motion. P2.2C Describe and analyze the motion that a velocity-time graph represents, given the graph. P2.2e Use the area under a velocity-time graph to calculate the distance traveled and the slope to calculate the acceleration. 1. (P2.1A) The picture below shows a ball rolling along a table at 1 second time intervals. What is the object s average velocity after 6 seconds? 2. (P2.1A) A car traveled along a straight road at +50 mi/h for 3.0 hours and then traveled on the same road at +35 mi/h for 1.5 hours. What was the car s average velocity over the entire trip? 3. (P2.1B) Answer the following questions regarding the motion diagrams of a ball rolling below. a. Which of the following diagrams shows the ball rolling with a constant velocity? b. Which of the following diagrams shows the ball rolling with a positive acceleration? c. Which of the following diagrams shows the ball rolling with a negative acceleration? d. Which of the following diagrams shows the ball rolling with a zero acceleration? 4. (P2.1C) Make a position time graph for each object in the table above. Time (s) Object A Object B (P2.1D)Answer the following questions using the position time graph below. a. What is the average velocity between 0 and 5 seconds? b. What is the average velocity between 0 and 10 seconds? c. What is the average velocity between 0 and 20 seconds? d. What is the instantaneous speed between 5 and 10 seconds? 6. (P2.1g) A child can push a shopping cart with an average velocity of 1.5 m/s west. How long would it take the child to push the cart down an aisle with a length of 9.3 m?

2 7. (P2.1g) It took 3.5 hours for a train to travel the distance between two cities at a speed of 120 miles/hr. How many miles lie between the two cities? 8. (P2.1g) A cat falls off the top of a dresser that is 2 meters above the ground. How long does it take to reach the ground? 9. (P2.2A) Which of the following are vectors? Which of the following are scalars? a. Distance e. Velocity b. Time d. Acceleration c. Displacement g. Mass d. Speed 10. (P2.2A) The length of a football field is 100 yards. A football player runs the entire length of the field and back in 24 seconds. a. What is the distance and the displacement of the football player? b. What is the speed and the velocity of the football player? 11. (P2.2B) With an average acceleration of 0.50 m/s 2, how long will it take a cyclist to bring a bicycle with an initial velocity of m/s to a complete stop? 12. (P2.2B) A car is accelerating at a rate of 5 m/s 2, if its initial velocity is 6 m/s, what is its velocity after 4 s? 13. (P2.2B) A ball is dropped from rest from a high building. What is the ball s velocity after 3 s? (Ignore air resistance). 14. (P2.2C) Draw a velocity time graph of a ball that is thrown straight up into the air and then returning to its original height. 15. (P2.2e) Use the velocity time graph below to answer the following questions: a. What is the displacement of the object between 2 s and 6 s? b. What is the acceleration of the object at 3 s? UNIT 2 Two-Dimensional Motion and Forces P2.2g P3.2d P3.4e Apply the independences of the vertical and horizontal initial velocities to solve projectile motion problems. Calculate all the forces on an object on an inclined plane and describe the object s motion based on the forces using free-body diagrams. Solve problems involving force, mass and acceleration in two dimensional projectile motion restricted to an initial horizontal velocity with no initial vertical velocity (e.g., a ball rolling of a table). 16. (P2.2g) A stone is thrown horizontally off a cliff. Assuming no air resistance: a. Describe what happens to the horizontal and vertical velocities of the stone as it falls. b. What is the direction of the acceleration of the stone at each moment as it falls? 17. (P2.2g) A person traveling on a train that is moving west at a constant speed throws a ball straight up into the air. The person and the train continues to travel on a straight horizontal track and air resistance is ignored. Where will the ball fall? 18. (P3.2d) A 50 kg box is at rest on a friction-less ramp. The ramp is at an angle of 25 to the ground. a. What is the normal force of the ramp on the box? b. What is the net force acting on the box? 19. (P3.2d) A 45 kg child slides down a frictionless slide at the park. The slide is inclined at an angle of 30 to the horizontal. a. What is the normal force acting on the child? b. What is the net force acting on the child?

3 20. (P3.4e) A cannon that is 15 m high shoots a ball horizontally with an initial speed of 10 m/s. Assuming no air resistance, how far away from the cannon will the ball land? 21. (P3.4e) Two balls, a GREEN and a WHITE, roll horizontally off a table that is 2 m above the ground. The GREEN ball has an initial speed of 10 m/s and the WHITE ball has an initial speed of 20 m/s. At what time will each ball take to reach the ground (assume no air resistance)? 22. (P3.4e) A plane flying horizontally at a constant speed releases a projectile. Where will the plane be when the projectile strikes the ground (assume no air resistance)? UNIT 3 Dynamics P3.2A P3.2C P3.3A P3.4A P3.4C Identify the magnitude and direction of everyday forces (e.g., wind, tension in ropes, pushes and pulls, weight). Calculate the net force acting on an object. Identify the action and reaction force from examples of forces in everyday situations (e.g., book on a table, walking across the floor, pushing open a door). Predict the change in motion of an object acted on by several forces. Solve problems involving forces, mass, and acceleration in linear motion (Newton s second law). 23. (P3.2A) Give examples of contact forces and field forces (a.k.a. forces at a distance or non-contact forces). 24. (P3.2A) What is the normal force? 25. (P3.2A) A 245 N crate is at rest on the floor. A person attempts to push it across the floor. The coefficient of static friction between the floor and the crate s What is the maximum force of static friction between the crate and the ground? 26. (P3.2A) Draw a free body diagram for each of the following situations: a. A sled at rest. b. A sled moving at a constant speed to the right. c. A sled accelerating to the right. 27. (P3.2C) An object that is falling towards the earth without the presence of air resistance is accelerating back to the earth. Does the acceleration increase, decrease, or remain the same during the fall? 28. (P3.2C) A motorcycle is slowing down in the forward direction. What is the direction of the net force acting on the motorcycle? 29. (P3.2C) The forces acting on a sailboat are 390 N north and 180 N east. The boat has a total mass of 270 kg. What is the magnitude of the resultant (net) force? 30. (P3.2C) Two forces acting on a 5 kg object are 7 N and 10N. The angle between the forces can be varied. What is the range of possible magnitudes of the net (resultant) force acting on the object? 31. (P3.3A) Describe Newton s Third Law of Motion. 32. (P3.3A) Identify the action-reaction forces for the following situations: a. Book on a table b. Pushing open a door c. Collision between small car and a large truck 33. (P3.4A) Describe Newton s First Law of Motion. 34. (P3.4A) What type of force is required to change an object s velocity or direction? 35. (P3.4A) The object to the right has four forces acting on it. The object was initially at rest. Which direction does the object move when the forces are applied? 36. (P3.4A) A 60 kg person stands on a scale in an elevator. a. What does the scale read when the elevator is moving up at a constant speed? b. What does the scale read when the elevator is moving down at a constant speed? c. What does the scale read when the elevator is accelerating downward at 1.5 m/s 2? d. What does the scale read when the elevator is accelerating upward at 1.5 m/s 2? 37. (P.3.4A) Describe what happened to the person s scale reading in c and d above.

4 38. (P3.4C) Describe Newton s 2 nd Law of Motion. 39. (P3.4C) A 5 kg object accelerates at 2 m/s 2. What is the net force acting on the object? 40. (P3.4C) A weightlifter applies a constant 1040N force upward to a barbell. The barbell has a mass of 100kg. What is the acceleration of the barbell? 41. (P.3.4C) Describe the relationship between mass and weight of an object when placed on two different planets. 42. (P3.4C) How does the mass of an object change when an objects weight is measured on the moon and on earth? 43. (P3.4C) Solve for the weight of a person whose mass is 100 kg if the acceleration due to gravity on the planet they are standing on is one-quarter that of the earth. UNIT 4 Circular Motion P2.2D P3.4D P3.6B P3.6d P3.6e P2.1h State that uniform circular motion involves acceleration without a change in speed. Identify the force(s) acting on objects moving with uniform circular motion (e.g., a car on a circular track, satellites in orbit). Predict how the gravitational force between objects changes when the distance between them changes. Calculate force, masses, or distance, given any three of these quantities, by applying the Law of Universal Gravitation, given the value of G. Draw arrows (vectors) to represent how the direction and magnitude of a force changes on an object in an elliptical orbit. Identify the changes in speed and direction in everyday examples of circular (rotation and revolution), periodic, and projectile motions. 44. (P2.2D) Describe the acceleration, velocity and speed of an object that is experiencing uniform circular motion. 45. (P3.4D). Identify the force(s) acting on the objects moving with uniform circular motion: a. a ball attached to a string b. a car on a circular track. c. a satellite in orbit. 46. (P3.6B) What will happen to the gravitational force if you do the following: a. double the distance between two masses. b. cut the distance in half between the two masses. 47. (P3.6d) What is the universal law of gravitation? 48. (P3.6d) Determine the force of gravitational attraction between the earth (m = 5.98x10 24 kg) and a 70kg physics student if the student is standing at sea level, a distance of 6.38x10 6 m from the earth s center. 49. (P3.6d) Suppose that you have a mass of 70 kg. How much mass must another object have in order for your body and the other object to attract each other with a force of 1 N when separated by 10 m? 50. (P3.6e) Draw vectors at each point of the on the diagram below to represent how the direction and magnitude of a force changes on an elliptical orbit. 51. (P2.1h) Describe the speed and direction of a car experiencing uniform circular motion. 52. (P2.1H) Describe the speed and direction of a pendulum that is swinging back and forth.

5 Velocity PHYSICS FINAL EXAM REVIEW KEY FIRST SEMESTER (01/2017) UNIT 1 Motion cm/s = m/s mi/h 3. a. C b. A c. B d. C 4. (P2.1C) Make a position time graph for each object in the table above. 5. a. 2 m/s b. 4 m/s c. 0 m/s d. 6 m/s Time (s) Object A Object B Time (s) Object A Object B s miles s 9. (P2.2A) Which of the following are vectors? Which of the following are scalars? a. Distance scalar e. Velocity vector b. Time scalar f. Acceleration vector c. Displacement vector g. Mass scalar d. Speed scalar 10. a. distance = 200 yards; displacement = 0 yards b. speed = 8.33 yards/sec; velocity = 0 yards/sec s m/s m/s 15. a. 60 m b. 10 m/s Time

6 UNIT 2 Two-Dimensional Motion and Forces 16. a. Horizontal velocity (v x ) is constant and is equal to the initial velocity in the x-direction. Vertical velocity (v y ) will decrease (becoming more negative) throughout its fall. b. The direction of acceleration is straight down and equal to -9.8 m/s The ball will fall back into the person's hand. 18. a. 444 N to the ramp b. 0 N 19. a N to the ramp b N down the ramp m s 22. Plane will be directly above the projectile UNIT 3 Dynamics 23. Contact forces: normal force, friction force, push, pull, string force, spring force Field forces: gravitational force, magnetic force, electric force 24. Normal force is the force exerted upon an object by the surface it sits upon. The normal force is to the surface N 26. a. OR b. c. 27. remains the same; 9.8 m/s backward direction N 30. Depending upon the angle, the resultant force could be between 3 N (the resultant force if angle is 180 ) and 17 N (the resultant force if angle is 0 ). If the angle is 90, the resultant force is 12.2 N. 31. For every force acting upon an object, there is an equal and opposite force acting upon a different object. 32. a. Force of book pushing down on table -- force of table pushing up on book (F N ) b. Force of you pushing door open -- force of door pushing back at you c. Force of small car hitting large car -- force of large care hitting small car 33. An object at rest will stay at rest unless acted upon by an unbalanced force. An object in motion will stay in constantvelocity, straight line motion unless acted upon by an unbalanced force. 34. unbalanced force

7 35. to the right 36. a. 588 N b. 588 N c. 498 N d. 678 N 37. c. Since the scale is accelerating downward, the net force is directed downward. This means the F N (the force the scale shows) is less than the F g. d. Since the scale is accelerating upward, the net force is directed upward. This means the F N (the force the scale shows) is greater than the F g 38. The sum of all the forces acting upon an object (F net ) is equal to the mass of that object times its acceleration N m/s 2 upward 41. The mass (quantity of matter) does not change regardless of where the object is located. Weight is a function of the acceleration due to the planet's gravity, so the weight of an object will be different on different planets. 42. mass does not change N UNIT 4 Circular Motion 44. In circular motion, acceleration is always directed toward the center (centripetal acceleration). Velocity is always directed forward in a straight line tangent to the circular path. Speed is constant. 45. a. tensional force in the string supplies centripetal force to keep object in a circular path. b. frictional force between the road and tires supplies centripetal force to keep object in a circular path. c. gravitational force between the satellite and planet supplies centripetal force to keep object in a circular path. 46 a. It is quartered (x 1/4) b. It is 4X greater 47. The force between two masses is proportional to the amount of mass in each object and is indirectly related (by the inverse square law) to the distance between the objects. F g = G m 1m 2 r N x kg The speed is constant (uniform) and the direction is changing. 52. The speed is changing and direction is changing. Speed is greatest at equilibrium, and speed reaches zero at maximum amplitude.