The tension force pulling the lower block

time graphs shows in figure 1 below best represents the motion of the car?

Two identical Mini Coopers A and B travel from Polokwane to Mankweng at constant velocities of 55 m/s and 45 m/s respectively. Car B is behind car A and the distance of separation between the two cars is 10.0 m.

x(t) = (3.00 m/s3)t3- (10.00 m/s2)t2 + (9.00 m/s)t – 3

Use the above information to answer questions 6 to 12.

10. The values of time(s) t between t = 0 and t = 2 s when the velocity of the particle is instantaneously at rest are
A) 0 s B) 2 s C) 0 and 2 s D) 0.6 and 1.6 s E) None of them

11. The acceleration(s) at each time t calculated in question 10 above are
A) – 20.00 m/s2 B) 16.00 m/s2 C) 8.80 & – 8.66 m/s2 D) – 20.00 & 16 ms2 E) None of them
2

A) 8.5 m/s	B) 9.5 m/s	C) 12.0 m/s D) 13.4 m/s	E) None of them

14. The position of the particle at t = 2.0 s
A) 12 m 72o along the +ve x axis B) 28.5 m 288o above the +ve x axis

17. A cricket ball is thrown vertically upwards and reaches a height of 18 m above the ground. On the way down it gets stuck in a tree that is 10 m above the ground. What is the resultant displacement of the ball?

A) 10 m downwards B) 10 m upwards C) 8 m downwards D) 8 m upwards E) None of them

20. Calculate the velocity at which the stone hits the ground.

A) 25.00 m /s B) – 34.84 m/s C) 0 m/s D) 34.84 m/s E) None of them

23. The initial velocity of the egg is
A) 4.9 m/s B) 49.1 m/s C) 30.0 m/s D) 98.1 m/s E) None of them

24. The highest point reached by the egg is
A) 9133 m B) 12.29 m C) 122.9 m D) 91.33 E) None of them

A) 90 o B) 30 o	C) 0 o	D) 180 o E) None of them

A) 77.0 m	B) 25.0 m C) 45.9 m	D) 103.1 m E) None of them

30. How long (whole motion) will the egg have travelled when it will be halfway the maximum height?

A) 3.54 s upward & 6.47 s downward C) Both 1.47 s upward & downward E) None of them

33. How long after the second ball is thrown do the two balls pass each other? A) 0.39s B) 3.90 s C) 7.80 s D) 1.10 s E) None of them

34. When the balls pass each other, how far are they above the juggler’s hands? A) 3.00 m B) 2.00 m C) 1.50 m D) 0.75 m E) None of them 5

37. The velocity of the ball as it strikes the wall is
A) 13.38 m/s B)14.86 m/s C) 20.00 m/s D) 1.18 m/s E) None of them

38. The direction of the velocity as it strikes the wall is
A) + x axis B) – x axis C) – y axis D) + y axis E) None of them

A) 9.05 m B) 0.07 m C) 1.79 m D) 9.12 m E) None of them

Hashim Amla, the former SA national cricket team captain, batted a ball with an initial upward velocity component of 20 m/s and a horizontal velocity component of 25 m/s. Use the above information to answer questions 42 to 46.

43. Time taken by the ball to reach its highest point is

A) 2.55 s	B) 2.14 s	C) 2.20 s	D) 2.04 s

A) 2.55 & 3.00 s B) 0.51 & 1.53 s C) 1.53 & 2.55 s D) 0.51 & 3.00 s E) None of them

46. The magnitude and direction of the initial velocity at which Amla batted the ball is A) 32 m/s & 38.7o above the ground B) 1025 m/s & 38.7o above the ground C) 32 m/s & 51.3o above the ground D) 20 m/s & 51.3o above the ground E) None of the above.

C) The frictional force in always in the same direction as the motion of the motion. D) The frictional force is always in the opposite direction as both the applied force and the motion of the object.

E) None of the above.

20 N

Figure 2

Use the above information to answer questions 51 to 54.

Consider now the same object in figure 2 being pushed at the same angle with the same applied force but on a rough surface.

Use the above information to answer questions 55 to 59.

58. The velocity after 5 s is
A) 0.75 m/s B) 0.00 m/s C) 1.25 m/s D) 2.50 m/s E) None of them

59. The distance travelled after 5 s is
A) 20.00 m B) 40.00 m C) 3.13 m D) 31.30 m E) None of them

60. ∑Fx =
A) Fcos θ = ma B) F – fk = ma C) Fcos θ - fk = ma D) Fsin 0o – fk = ma E) None of them

61. Its acceleration will be
A) 9.81 m.s-2 B) 7.85 m.s-2 C) 17.66 m.s-2 D) 6.87 m.s-2 E) None of them

Figure 5 indicates three similar blocks each of mass 4 kg, connected by massless strings and are being pulled to the right with a 12 N force across a horizontal, frictionless surface. The tension in the centre string is T.

	B) 8 N	C) 24 N	D) 28 N	E) None of them

E) None of them

A) 3 m/s2 B) 2 m/s2	C) 1 m/s2	D) 0 m/s2 E) None of them

66. The force of static friction between the top and bottom blocks is

frictionless pulleys. The acceleration of the system is 3.2 m/s2 to the left and the

surfaces are rough. The coefficient of friction between the surface and block of 4.0

67. The coefficient of kinetic friction between the surface and the block of 2.0 kg is

A) 0.2	B) 0.4	C) 0.8	D) 2.0

A) 32.3 N	B) 44.2 N	C) 52.9 N	D) 64.5 N	E) None of them

70. Assume that the surfaces in figure 7 are smooth and the pulleys are not

71. The new acceleration will be
A) 1.4 m/s2 B) 4.9 m/s2 C) 6.4 m/s2

D) 8.2 m/s2 E) None of them

		C) 25.2 N	D) 44.7 N
	B) 19.6 N	C) 25.2 N	D) 44.7 N
		C) 15.3 N	D) 11.2 N	E) None of them
A) 39.3 N	B) 19.6 N	C) 15.3 N	D) 11.2 N	E) None of them

74. What is the tension in the rope attached to the wall?

Figure 9
Use the above information to answer questions 76 to 87.

79. For block Z, ∑Fy =
A) T – mZgsin37o = mZa B) mZg – T = mZa C) T′ – mZg = mZa

D) T′– T + mZgsin37o = mZa

81. The acceleration of the system is

A) 0.39 m.s-2 B) 4.58 m.s-2 C) 3.99 m.s-2 D) 3.50 m.s-2 E) None of them

If in the figure 9 above, the surface is now rough, and the coefficient of kinetic friction

is 0.27.

85. The new acceleration of the system is
A) 0.39 m.s-2 B) 4.58 m.s-2 C) 3.99 m.s-2 D) 3.50 m.s-2 E) None of them

86. The new tension T of the system is
A) 69.0 N B) 69.8 N C) 72.0 N D) 62.8 N E) None of them