x v 2 = x a mx 2 t 2 Exam 1--PHYS 101--F17 Name: Multiple Choice Identify the choice that best completes the statement or answers the question.

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1 Name: Exam 1--PHYS 101--F17 Multiple Choice Identify the choice that best completes the statement or answers the question. 1. Which of these best approximates the area of one side on your calculator (the side with the numbers)? a m 2 b. 0.2 m 2 c. 2.0 m 2 d. 20. m 2 2. Which of these is a typical person s running speed? a. 0.4 m/s b. 4 m/s c. 40 m/s d. 400 m/s 3. Which of these equations is dimensionally correct? I. x v 2 = x a II. mv 2 = mxa+ 1 2 III. x=2vt 3x v2 ax mx 2 t 2 a. II & III b. I & III c. II d. III e. all of these are correct 4. If the acceleration of an object, a, is related to the velocity v, according to the relation a=bv, what are the units for the constant B? a. s 2 /m b. 1/s c. m/s 2 d. s How many significant figures should the solution to this expression have? a. 4 b. 3 c. 2 d. 1 e The standard for the second is based on which of the following? a. the time it takes light to travels a particular distance b. how long it takes a cesium atom to vibrate c. the period of a pendulum in France d. the motion of the Sun e. the time for an atom to traverse a particular silicon sphere 7. Describe the main difference between the metric system and the US Customary System. a. In the metric system, each unit conversion has unrelated conversion factors, while in the US customary system, unit changes are based on powers of 2. b. In the metric system, unit changes are based on powers of 10, while in the US customary system, each unit conversion has unrelated conversion factors. c. In the metric system, unit changes are based on powers of 2, while in the US customary system, each unit conversion has unrelated conversion factors. d. In the metric system, each unit conversion has unrelated conversion factors, while in the US customary system, unit changes are based on powers of 10. 1

2 8. This coordinate system shows the location of a line from the origin to (-5.0,-2.0). What is the angle of this line as measured from the +x-axis? 11. You throw a ball up with an initial speed of 30 m/s. How high does it travel? a. 90 m b. 30 m c. 50 m d. 20 m e. 10 m a. 250 b. 200 c. 24 d. 68 e Two bikes are 100 meters apart. They begin travelling towards one another. One travels with a speed of 4 m/s; the other travels with a speed of 3 m/s. How far apart are the two bikes after 10 seconds? 9. For the above figure, what is the length of the line? a. 5.4 b. 25 c. 10 d. 7.0 e The speed limit on some interstate highways is roughly 90 miles/hour. How many meters per second is this? (1 mile = 1609 meters) a. 120 m/s b. 140,000 m/s c. 200 m/s d. 20 m/s e. 40 m/s a. 10 m b. 90 m c. 70 m d. 60 m e. 30 m 13. A motorcycle moving at a constant velocity suddenly accelerates at a rate of 4.0 m/s 2 to a speed of 35 m/s in 5.0s. What was the initial speed of the motorcycle? a. 9.0 m/s b. 15 m/s c. 32 m/s d. 140 m/s e. 55 m/s 2

3 14. A swan on a lake gets airborne by flapping its wings and running on top of the water. If the swan must reach a velocity of 4.0 m/s to take off and it accelerates from rest at an average rate of 0.20 m/s 2, how far will it travel before becoming airborne? 17. You travel from A to B and then, back to C. What is your displacement and distance traveled? a. distance = 6 ; displacement = +2 b. distance = 4 ; displacement = +6 c. distance = 2 ; displacement = -2 d. distance = 5 ; displacement = +2 e. distance = 6 ; displacement = You drop an object. Which of these represents the position versus time graph? a. 30. m b. 120 m c. 80. m d. 40. m e. 8.0 m 15. You drop two rocks off of a bridge. The first has twice the mass of the second rock. Which will have the greater velocity when they hit the ground? a. the first rock b. the second rock c. both will have the same veloctiy d. it depends on how long they ve fallen a. a b. b c. c d. d 19. Consider this graph. Describe the motion of the object for these three time periods: A, B, and C. 16. Which of these statements about kinematics is true? I. Speed is the magnitude of velocity. II. Acceleration describes how the velocity changes with time. III. An object with negative acceleration is always slowing down. IV. An object is speeding up; its acceleration is always positive. a. I & II b. III & IV c. I, II, and III d. I & III e. all are correct a. A: the object has positive acceleration B: the object has a constant speed C: the object has a constant speed b. A: the object is slowing down B: the object is speeding up C: the object is slowing down c. A: the object has negative acceleration B: the object has zero acceleration C: the object has a constant, negative velocity d. A: the object has a negative velocity B: the object has a positive velocity C: the object has a negative velocity 3

4 20. A car has negative acceleration and positive velocity. Which of these position versus time graphs represent this motion? 22. Consider this graph. What is the instantaneous velocity of the object at t=7 seconds? a. a b. b c. c d. d 21. In this graph of velocity vs time, what is the instantaneous acceleration at point B? a. -4 m/s b. -1 m/s c. -2 m/s d. 0 m/s e m/s 23. Consider this graph of velocity versus time. Estimate the distance the object moves between t=0 and 10 seconds. a. 0.5 m/s 2 b. 1.6 m/s 2 c. 4 m/s 2 d. 2.5 m/s 2 e. 0 m/s 2 a. 96 m b. 24 m c. 120 m d. 72 m 24. Consider the previous graph. What is the average acceleration between t=2 and 8 s? a. 9.0 m/s 2 b. 1.5 m/s 2 c. 1.0 m/s 2 d. 12 m/s 2 e m/s 2 4

5 25. Consider these 2 vectors. What is the direction of their sum, A ä + B ä? Aä = 2.00 units along the -y axis (the negative-y axis) Bä = 9.0 units at 60.0 degrees above the +x axis 28. Please estimate your grade on this exam. You will receive credit for this answer regardless of your answer. a. A b. B c. C d. D e. F a. 65 above the +x-axis b. 35 above the +x-axis c. 52 above the +x-axis d. 33 below the +x-axis e. 74 above the +x-axis 26. Consider these vectors. What is B-A? a. a b. b c. c d. d 27. A vector has a negative x-component and a positive y-component. The magnitude of the y-component is bigger than the x-component. Which of these is the only appropriate angle, measured from the +x axis, for this vector? a. 80 b. 290 c. 190 d. 150 e

6 ID: A Exam 1--PHYS 101--F17 Answer Section MULTIPLE CHOICE 1. ANS: A PTS: 1 REF: F17 2. ANS: B PTS: 1 REF: F17 3. ANS: A PTS: 1 REF: F17 4. ANS: B PTS: 1 REF: F17 5. ANS: B PTS: 1 REF: F17 6. ANS: B PTS: 1 REF: F17 7. ANS: B PTS: 1 REF: F17, OXT 8. ANS: B PTS: 1 REF: F17 9. ANS: A PTS: 1 REF: F ANS: E PTS: 1 REF: F17, OXT 11. ANS: C PTS: 1 REF: F ANS: E PTS: 1 REF: F ANS: B PTS: 1 REF: F17 -- OXT 14. ANS: D PTS: 1 REF: F17--OXT 15. ANS: C PTS: 1 REF: F ANS: A PTS: 1 REF: F ANS: E PTS: 1 REF: F ANS: C PTS: 1 REF: F ANS: C PTS: 1 REF: F ANS: D PTS: 1 REF: F ANS: E PTS: 1 REF: F ANS: B PTS: 1 REF: F ANS: A PTS: 1 REF: F17--OXT 24. ANS: C PTS: 1 REF: F ANS: C PTS: 1 REF: F ANS: B PTS: 1 REF: F ANS: E PTS: 1 REF: F ANS: A PTS: 1 1