A uniform rod is 2.00 m long and has mass 1.80 kg. A 2.40-kg clamp is attached to the rod. How far should the center of gravity of the clamp be from the left-hand end of the rod in order for the center of gravity of the composite object to be 1.20 m from the left-hand end of the rod?

(II) The center of gravity of a loaded truck depends on how the truck is packed. If it is 4.0 m high and 2.4 m wide, and its cg is 2.2 m above the ground, on how steep a slope can the truck be parked without tipping over (Fig. 12–77)?

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A 50-story building is being planned. It is to be 180.0 m high with a base 46.0 m by 76.0 m. Its total mass will be about 1.8 x 10⁷ kg, and its weight therefore about 1.8 x 10⁸ N. Suppose a 200-km/h wind exerts a force of 950N/m² over the 76.0-m-wide face (Fig. 12–86). Calculate the torque about the potential pivot point, the rear edge of the building (where F→_E acts in Fig. 12–86), and determine whether the building will topple. Assume the total force of the wind acts at the midpoint of the building’s face, and that the building is not anchored in bedrock. [Hint: F→_E in Fig. 12–86 represents the force that the Earth would exert on the building in the case where the building would just begin to tip.]

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The forces acting on an 85,000-kg aircraft flying at constant velocity are shown in Fig. 12–108. The engine thrust, F_T = 5.0 x 10⁵ N, acts on a line 1.6 m below the cm. Determine the drag force F_D and the distance above the cm that it acts. Assume F→_D and F→_T are horizontal. ( F→_L is the “lift” force on the wing.)

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A 70 kg, 1.90 m man doing push-ups holds himself in place making 20° with the floor. His feet and arms are, respectively, 1.15 m below and 0.4 m above his center of mass. You may model him as a thin, long board, and assume his arms and feet are perpendicular to the floor. How much force does the floor apply to each of his hands? (Use g=10 m/s².)