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A rod of length 4.00 m with negligible mass is hinged to a wall. A rope attached to the end of the rod runs up to the wall at an angle of exactly 45°, helping support the rod, while a sign of weight 10.0 N is hanging by two ropes attached to the bottom of the rod. The ropes make an angle of exactly 30° with the rod as shown in Figure P14.79. Another sign with a weight of 10.0 N is attached to the top of the rod with its center of mass at the midpoint of the rod. The entire system is in equilibrium. Find the magnitude of the tension in the rope above the rod that is also attached to the wall.
FIGURE P14.79 Problems 79 and 80.
N In Problem 79, find the magnitude of the vertical and horizontal components of the force that the hinge must exert on the rod to keep the system in equilibrium.
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Chapter 14 Solutions
Physics for Scientists and Engineers: Foundations and Connections
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