PLEASE DO NOT WRITE ON THIS PACKAGE Review 2

1. Convert 0.0215 m to mm A. 0.215 mm B. 2.15 mm C. 21.5 mm D. 215 mm

2. If a man is 6 foot 4 inches tall, what is his approximate height in centimeters? (1 in. = 2.54 cm) A. 230 B. 190 C. 150 D. 120

3. The terminal velocity of a drop of water falling through the atmosphere is v = (2/9) (r2 g p/n) where v is the velocity of the drop in m/s; r is the radius of the drop in m; g is the acceleration of gravity in m/s2 and p is the density of water in kg/m3. What must be the units of n, the coefficient of viscosity of the air through which the drop falls? A. kg m/s B. m s/kg C. kg s2/m D. kg/m s

Use the following graph to answer questions #4-6

4. During the first 8 s A. C has decreasing velocity and D has increasing velocity B. C and D both have decreasing velocities. C. C and D have the same velocity D. C has the same average velocity as D.

5. During the first 8 s A. the magnitude of the acceleration of C is greater than the magnitude of D's acceleration. B. their accelerations are equal in magnitude but opposite in sign C. their accelerations are equal in magnitude and equal in sign

6. Based on all the graphical information A. they meet at the same position at t = 8 s. B. they will meet at the same position, at t = 10 s. C. they will never meet at the same position D. not enough information is given to decide if they meet.

7. If a car accelerates from rest in the positive direction A. its final velocity is zero. B. its initial position is zero. C. its initial velocity is zero. D. its acceleration is negative.

8. In this problem "up" is taken to be positive. A ball is thrown straight up in the air, at the very top its A. velocity is negative B. acceleration is zero. C. its acceleration is 9.8 m/s2 D. its acceleration is -9.8 m/s2

9. In this problem "up" is taken to be positive. A falling object has A. positive acceleration and positive velocity B. negative acceleration and negative velocity C. positive acceleration and negative velocity. D. negative acceleration and positive velocity.

10. Ball A is thrown upward at the same time as ball B and with half the speed of ball B. How much higher does B go than A? A. 8 times B. 4 times. C. 2 times D. Not enough information is given to answer this question PLEASE DO NOT WRITE ON THIS PACKAGE 11. If the average speed of a plane is 500 km per hour, how long will it take to fly 125 km? A. 4.00 h B. 2.00 h C. 0.50 h D. 0.25 h

12. Applying the brakes to a car traveling at 45 km/h provides an acceleration of 5.0 m/s2 in the opposite direction. How long will it take the car to stop? A. 0.40 s B. 2.5 s C. 5.0 s D. 9.0 s

13. The speeds of a body at the ends of five successive seconds are: 180, 360, 540, 720, 900 m/h. What is the acceleration of the body? A. 0.05 m/s2 B. 20 m/s2 C. 180 m/s2 D. 180 m/h2

14. "An object is observed to move in a straight line. Some aspect of the motion of this object is plotted as a function of time in the following graph." The slope of the dashed line in the graph above represents ___. A. an instantaneous position B. an average position C. a distance traveled D. an instantaneous speed E. an average speed

15. "An object is observed to move in a straight line. Some aspect of the motion of this object is plotted as a function of time in the following graph." The shaded area in the graph above represents ___.

A. an average acceleration B. an instantaneous position C. a change in position or a distance traveled D. a change in speed E. an instantaneous speed

16. The speed of an object moving in a straight line changes with time as in the figure below." During which time interval did the maximum value of the magnitude of the instantaneous acceleration occur? A. t = 0 to t = 1s B. t = 1 to t = 2s C. t = 2 to t = 3s D. t = 3 to t = 4s E. t = 4 to t = 5s

17. The speed of an object moving in a straight line changes with time as in the figure below." During which time interval was the magnitude of the average acceleration least?

A. t = 0 to t = 1s B. t = 1 to t = 2s C. t = 2 to t = 3s D. t = 3 to t = 4s E. t = 4 to t = 5s

18. If you drive west at 20 km/h for one hour, then drive east at 15 km/h for one hour, your net displacement will be A. 35 km west B. 5 km east C. 35 km east. D. 5 km west

19. A 200-lb force is pulling on an object, as shown. The sign of the x and y components of the force are A. x (positive), y (positive). B. x (positive), y (negative C. x (negative), y (positive D. x (negative), y (negative).

20. Three boys each pull with a 20-N force on the same object. The resultant force will be A. zero B. 20 N to the left C. 20 N up D. 20 N down. PLEASE DO NOT WRITE ON THIS PACKAGE

21. Two vectors, R and S, are known: If vector R is subtracted from vector S, the vector T = S - R is A. B. C. D.

22. If the acceleration vector of a body is perpendicular to the velocity vector, which of the following must be true? A. The speed is changing B. The direction is changing. C. Both the speed and the direction are changing D. The direction is not changing.

23. A vector of magnitude 10 has an angle with the positive x-axis (East) of 120 degrees. What are its components? A. 5 and 8.7 B. -5 and 8.7 C. 5 and -8.7 D. 5 and -8.7

24. Which of the following is constant for projectiles? A. vx B. vy C. xf D. yf

25. Which of the following must be zero for a projectile to be at its maximum height? A. vxf B. vyf C. yf D. xf

26. You hit a handball too hard and it lands, moving horizontally, on top of a roof. If its original velocity was vo at an angle q above the horizontal, then the velocity it lands on the roof with is A. zero B. vo sin q C. vo cos q D. 2vo

27. Force is a vector quantity measured in units of Newtons, N. What must be the angle between two concurrently acting forces of 5 N and 3 N respectively if the resultant vector is 8 N? A. 0° B. 45° C. 90° D. 180°

28. For which of the vector diagrams is it true that T1 + T2 = T3? A. C.

B. D.

29. An airplane is flying in the presence of a 100 km/h wind directed due north. What must be the velocity and heading of the plane if it is to maintain a velocity of 500 km/h due east with respect to the ground A. 510 km/h E B. 300 km/h SE C. 510 km/h 11° South of East D. 600 km/h E

30. What must be the minimum velocity of a projectile launched from ground level over a flat, horizontal if it is to strike a target 100 meters away? A. 19.6 m/s B. 31.3 m/s C. 98.0 m/s D. 980 m/s

31. An arrow is shot at an angle of 30° above the horizontal with a speed of 29.4 m/s. How long will it take for the arrow to strike the ground? A. 1 s B. 2 s C. 3 s D. 4 s

32. Which trajectory best describes a ball rolling down a curved ramp that ends at point P? A. A B. B C. C D. D PLEASE DO NOT WRITE ON THIS PACKAGE

33. A packing crate slides down an inclined ramp at constant velocity. Thus we can deduce that A. a frictional force is acting on it B. a net force is acting on it C. it may be accelerating D. Gravity is not acting on it.

34.

A rope, tied between a motor and a crate, can pull the crate up a hill of ice (assume no friction) at constant velocity. The free-body diagram of the crate should contain _____ force(s) A. one B. two C. three D. four

35.

If two identical masses, attached by a massless cord passing over a massless, frictionless pulley of an Atwood's machine (at different heights), are released A. the lower mass will go down B. the higher mass will go down C. the masses will not move D. the motion will depend on the actual value of each mass

36. The same horizontal force is applied to objects of different mass. Which of the following graphs illustrates the experimental results? A. B. C. D.

37. A decoration, of mass M, is suspended by a string from the ceiling inside an elevator. The elevator is traveling upward with a constant speed. The tension in the string is A. equal to Mg. B. less than Mg. C. greater than Mg. D. impossible to tell without knowing the speed

38.

Two identical masses are attached by a light string that passes over a small pulley, as shown. The table and the pulley are frictionless. The system is moving A. with an acceleration less than g. B. with an acceleration equal to g. C. with an acceleration greater than g. D. at constant speed

39. A roller coaster car does a loop-the-loop. When it is upside down at the very top, which of the following is true? A. The normal force and the weight are in opposite directions B. The normal force and the weight are perpendicular to each other C. The weight is zero D. The normal force and the weight are in the same direction

40. A 2 kg box sits on a 3 kg box which sits on a 5 kg box. The 5 kg box rests on a table top. What is the normal force exerted on the 5 kg box by the table to A. 19.6 N B. 29.4 N C. 49 N D. 98 N PLEASE DO NOT WRITE ON THIS PACKAGE

41. A car pulls on a rope tied to a tree with a force of 1000 Newtons. Which of the following is not true A. The rope pulls on the tree with a force of 1000 Newtons. B. The tree pulls on the rope with a force of 1000 Newtons. C. The tension in the rope is 2000 Newtons. D. The tension in the rope is 1000 Newtons

42. A non-zero net force acting on a body will have which effect? A. The velocity of the body will remain constant B. The velocity of the body remains constant but the direction in which the body moves will change. C. The velocity of the body will change. D. None of the above.

43. Body A has a mass that is twice as great as that of body B. If a force acting on body A is half the value of a force acting on body B, which statement is true? A. The acceleration of A will be twice that of B B. The acceleration of A will be half that of B. C. The acceleration of A will be equal to that of B. D. The acceleration of A will be one fourth that of B.

44. What is the magnitude of the net force required to impart an acceleration of magnitude 10 m/s2 to a body with a mass of 2.0 kg? A. 0.2 N B. 5 N C. 12 N D. 20 N

45. Which graph best represents the relation between the force of gravity and the mass of a free- falling body? A. B. C. D.

46. After a rocket is launched, its engines are shut off. The rocket continues to move in a straight line at constant speed. This is an example of A. acceleration B. inertia C. gravitation D. action-reaction.

47. What is the impulse shown in the following figure? A. 225 Ns B. 450 Ns C. 900 Ns D. 1000 Ns

48. A 12000 kg railroad car traveling at 10 m/s strikes and couples with a 6000 kg caboose at rest. What is the speed of the final combination? A. 3.3 m/s B. 5.0 m/s C. 6.7 m/s D. 10 m/s

49. A tennis ball is hit with a tennis racket and the change in the momentum of the ball is 4 kg m/s. If the collision time of the ball and racket is 0.01 seconds, what is the magnitude of the force exerted by the ball on the racket? A. 2.5 x 10-3 N B. 4 x 10-2 N C. 3.99 N D. 400 N

50. A 160-pound jogger runs at a constant speed. What is his momentum if he covers 100 yards in 10 seconds? A. 6 ft lb /s B. 16 slug ft /s C. 100 ft lb /s D. 150 slug ft /s