13. FT A L m The diagram shows an object of mass #7 attached to a bar of length " by a short cable. The left end of the bar is held up by a hinge, attached to the wall. The bar is maintained in its horizontal orientation by a longer cable, attached from the end of the rod to the wall. The long cable makes an angle o with the bar and has tension FT. The mass of the bar is not negligible, The cables are assumed to have uniform linear density, the hinge is assumed to be frictionless and to have negligible radius, and the mass of the bar is assumed to be uniformly distributed along the length of the bar. Students calculate the theoretical tension in the long cable and then measure the actual tension in the cable. The measured tension is more than the theoretical tension. If the measurement is correct, which of the following could account for the discrepancy? Page 10 of 14 AP Physics C: Mechanics Scaring Quide Unit 5.1 Torque and Rotational Statics (A) The radius of the hinge is not negligible. B) The linear density of the short cable increases vertically. (C) The linear density of the bar decreases with distance from the wall. D) The rotational inertia of the bar about the hinge is less than $ MI?. (Ey The rotational inertia of the bar about the hinge is greater than ME".14. P C R Q A horizontal rod is supported at each end by ropes / and IT, which are attached to the rod at points ) and Q. respectively, as shown in the figure. The two ropes have negligible mass, and the rod has a nonuniform mass distribution such that the rod's center of mass is at point It. Point ( is the center of the rod. The rod remains horizontal. Which of the following vectors could represent the tensions Ty and Try in ropes I and IT, respectively, and the weight W of the rod? AP Physics C: Mechanics Page 11 of 16 Unit 5.1 Torque and Rotational Statics [A) W (B) W