1. 1. Rank the work done by the force from greatest to least. a)F=B >A > D > C >Ec) E > C > A=D > B >F b)F > B > A=D >C > Ed) F > B > C > A=D > E B Tips: greatest is F Least is D That eliminates answer c)

2. 2. If all of the blocks started at rest, rank the final speed from greatest to least a)F=B >A > D > C >Ec) E > C > A=D > B >F b)F > B > A=D >C > Ed) F > B > C > A=D > E B  K = W net, so greatest final speed is the one which has greatest WORK

3. 3. Rank the inertia of each block from greatest to least a)C=E >A > B > D > Fc) C > E > A > B > D >F b)F > B > A=D >C > Ed) F > C=E > A > B > D A Tips: greatest is C and E Least is D Only one applies

4. 4. Rank the normal force applied by the surface to each block from greatest to least a)F=B > D > A > C > Ec) D=A > F=B > C > E b)E > C > A > F=B > Dd) D > F=B > A > C > E D Tips: greatest is D Least is E eliminates a) and b)

5. 5. A coin lies on the top of a turntable at a distance R from the center. The coefficient of static friction between the coin and turntable is  s. What is the maximum speed that the turntable can go before the coin will slide off? a)c) b)d) A (Tips: can eliminate b and d based on wrong units) Draw a diagram and FBD to solve

6. 6. At the moment of the car’s location its acceleration is? a)c) b) d) B

7. 7. At the moment of the car’s location, its velocity is? a)c) b) d) C

8. 9. Determine the acceleration of the box as it slides down the ramp. a) b) c) d) B Tips: can eliminate a) since it is accel down incline due only to gravity can eliminate d) since it is a force not an acceleration Draw a diagram and FBD to solve

9. a)5.60 m b)8.10 m c) 3.35 m d) 15.2 m A Tip: can eliminate b) and d) since without friction max height is 8.1m (E B =E T and all K at bottom transforms to Ug at top). Friction removes energy so that sled will not go as high and h < 8.1

10. a)11 N b)25 N c) 36 N d) 42 N Tip: can eliminate a) and b) since F T must be greater than mg if pendulum mass is to move in a circle Isolated system- E is conserved Object is moving in circle, so there is FC and that is provided by the tension and gravity h FgFg FTFT C

11. D a)U O = U A = U B c) U O - U A = 2(U A – U B ) b)U A - U B = 2U O d) U A - U B = U O - U A This is about the potential differences between the points O, A, and B

12. D a)3.4 s b)17.1 s c)10.6 s d) 24.5 s If the chair is pulling up the hill at constant velocity, it is balancing gravity

13. A, the larger the vertical component of the initial velocity, the longer the time in air and therefore the higher. Rank the balls from smallest to largest maximum height a)C < B < A b)A < B < C c)A = B = C d) A = C < B Three soccer balls are kicked to the left at the same speed as shown. Ball A is kicked to the left at an angle of 60 o above the horizontal, ball B is kicked 45 o above the horizontal, and ball C is kicked 30 o above the horizontal.

14. A, the larger the vertical component of the initial velocity, the longer the time in air and therefore the higher. Rank the ball’s time in air from smallest to largest a)C < B < A b)A < B < C c)A = B = C d) A = C < B Three soccer balls are kicked to the left at the same speed as shown. Ball A is kicked to the left at an angle of 60 o above the horizontal, ball B is kicked 45 o above the horizontal, and ball C is kicked 30 o above the horizontal.

15. D, the range depends both on the time in air and the horizontal velocity. As the angle is increased, the time in air increases, but horizontal component of velocity decreases. Up until 45 o, this tradeoff works to increase range; beyond 45 o, range decreases. Complimentary launch angles have the same range. (This is only for projectiles launched over level ground) Rank the ball’s range from smallest to largest a)C < B < A b)A < B < C c)A = B = C d) A = C < B Three soccer balls are kicked to the left at the same speed as shown. Ball A is kicked to the left at an angle of 60 o above the horizontal, ball B is kicked 45 o above the horizontal, and ball C is kicked 30 o above the horizontal.

16. C (only for projectiles launched over level ground) Rank the ball’s impact speed from smallest to largest a)C < B < A b)A < B < C c)A = B = C d) A = C < B Three soccer balls are kicked to the left at the same speed as shown. Ball A is kicked to the left at an angle of 60 o above the horizontal, ball B is kicked 45 o above the horizontal, and ball C is kicked 30 o above the horizontal.

17. C (Use g = 10 m/s 2 ) a)1000 N b)600 N c)500 N d) 400 N The 500 N force is not strong enough to overcome the max static friction and therefore the block remains stationary with the 500 N force being balanced by fs.

18. A a)g/5 b)g/4 c)g/3 d) g FgFg If we treat the two blocks, string and pulley as a system then the tension is an internal force (force acting between the parts of the system) and it does not contribute to the net force.

19. B a)(1/5)mg b)(4/5)mg c)(1/3)mg d) mg FgFg To find tension, we cannot look at the whole system since tension is internal to the system. With the acceleration of the system known (and therefore we know acceleration of each block), pick just one block to find the force of tension. Best to pick the easier block to analyze. For the 4m block: A block of mass 4m can move without friction on a horizontal table. This block is attached to another block of mass m by a string that passes over a frictionless pulley. If the masses of the string and pulley are negligible, what is the magnitude of the tension of the string?

20. B, work is area under F-x curve a)80 J b)185 J c)275 J d) 365 J What is the work done on the object when it is moved from 0 to 9.0m?

21. A a)8.6 m/s 2 b)6.1 m/s 2 c)275 m/s 2 d) 365 m/s 2 If the object started from rest at the origin, what is its speed at 9.0 m

22. D a)about 20 m/s b)about 10 m/s c)about 5 m/s d) 0 m/s A ball is thrown straight up. At the top of its path its instantaneous speed is

23. B a)about 20 m/s b)about 10 m/s c)about 5 m/s d) 0 m/s A ball is thrown straight up. At the top of its path its acceleration is

24. 4

25. D, net force must be up a)Less than 0 b)Between 0 and Mg c)Equal to Mg d) Greater than Mg

26. a)The car b)The truck c)Both will stop same distance d) Cant tell without masses C The acceleration is independent of the mass

27. D a)F/m b)F/(2m) c)F/(3m) d) F/(4m) Since the string is ideal, the blocks have the same acceleration and we can treat the two blocks and string as a system. The tension is an internal force (force acting between the parts of the system) and it does not contribute to the net force of the system. What is the acceleration of the less massive box?

28. D a)F b)F/2 c)F/3 d) F/4 What is the tension force in the string between the boxes? To find tension, we use the acceleration found and look at just one of the blocks. Best to pick the easier block to analyze. For the m block:

29. B a)0.87g b)0.71g c)0.5g d) g Tip: can eliminate d) since it is not in free fall on the ramp INCLINE

30. B a)h=0; v=450m/s b)h=450m; v=0m/s c)h=450m; v=10m/s

31. C a)K = 200,000J; h=20m; v=63.2m/s b)K = 0; h=20m; v=0m/s c)K = 250,000J; h=20m; v=70.7m/s d)K = 200,000J; h=25m; v=70.7m/s

32. B a)a c = 714m/s 2 ; F c =71,400N; F N =71,400N b)a c = 714m/s 2 ; F c =71,400N; F N =70,400N c)a c = 714m/s 2 ; F c =71,400N; F N =72,400N FgFg FNFN