(a) Explain why the stability of a person against a toppling force is increased by spreading the legs as shown in Fig. 1.7. (b) Calculate the force required to topple a person of mass = 70 kg, standing with his feet spread 0.9 m apart as shown in Fig. 1.7. Assume the person does not slide and the weight of the person is equally distributed on both feet. 8 Chapter 1 Static Forces 1.2m 0.9 m FIGURE 1.7 Increased stability resulting from spreading the legs.