5.28 An object is subjected to the forces shown in Fig. 5-25. What single force F applied at a point on the x-axis will balance these forces? (First find its components, and then find the force.) Where on the x-axis should the force be applied? Ans. Fx = 232 N. F, = -338 N; F = 410 N at -55.5"; at x = 2.14 m 68 EQUILIBRIUM OF A RIGID BODY UNDER COPLANAR FORCES [CHAP. 5 300 N 200 N 2.30 m 1 1.50 m 150 N Fig. 5-25 5.29 The solid uniform disk of radius b shown in Fig. 5-26 can turn freely on an axle through its center. A hole of diameter D is drilled through the disk; its center is a distance r from the axle. The weight of the material drilled out is Fox. Find the weight Fi of an object hung from a string wound on the disk that will hold the disk at equilibrium in the position shown. Ans. Fw = Fux(r/b) cos # Fig. 5-26