09). If a rock is thrown up vertically with an initial speed of v0 m/s, the magnitudes of its velocity and acceleration, Vm and am , at its maximum height, respectively, are: A). Vm = v0 m/s and am = g m/s2 B). Vm = 0 m/S and am = 0 m/32 C). vm = 0 m/s and am = g m/S2 D). vm = V0 fm/s and am = gf m/32 10). At a NASA research center, free-fall (simulated micro gravity) research is performed by dropping experiment packages from the top of an evacuated shaft. If the shaft allows for a free fall of 340 m and the packages are released from rest at the top, for how long does the experiment experience micro-gravity conditions? A). 8.3 S B). 75 C). 7.63 D). 8.9s 11). A rock is thrown from a point 0 with an initial speed of v0 at an angle (9 above the horizontal as shown in the gure at right. It reaches maximum height at point T and lands at a point A which is at the same horizontal level as 0. Let 177. be the velocity at T and 17A is the velocity the instant before it hits the ground at A. Which of the following statements are correct? p). VT 2 v 0 sinHi q). Acceleration at T is gj r). VAX : v 0 cos (9 3). VA}, 2 v 0 sin 19 A). All B). r & s only C).p, r, & S only D). q & s only 12). For the projectile shown at right, yf= 40 m, w; = 50 m/s and 6:45 0. Neglect air friction. Y-component of the projectile's velocity the instant before it lands at B is: A). , 35.6 m/s B). 29.5 m/S C). 45.] m/s D). 39.3 m/s 13). Which one of the following best describes the net force acting on an object? A). The entity that causes a displacement of that object. B). Algebraic sum of the magnitudes of all forces acting on that object. C). The entity that changes the acceleration of that object. D). The entity that changes the velocity of that object 14). If the only two forces acting on the 3 kg mass are as shown at right, its acceleration is: P 2 : '3i + 5f N A). 155+18j'm /s2 B). 5+6}' m / s2 15', = 185+ 13.} N ': A. 2 t A' 2 C).51+6jm/s D).71+6Jm/s M=3kg 15). At t = 0 s, the velocity of an object of mass 2 kg is 170 : 5 In 6} m/s. Four seconds later, its velocity is 174 = 3i\" 12jm/s. Average net force FM exerted on the object during this time period is: A). f3j'N B). f9j'N C). 6}' N D). 2f6j'N 16). A mass m=20 kg is pulled up a frictionless surface at constant velocity as shown in the gure at right. The Surface makes and angle 6:25 0 with the horizontal. The rope that attaches the mass to the scale is massless and parallel to the surface. The reading on the scale is: A). 118.4N B). 142.2N C). 82.8N D). 177.6N