Chapter 1, Problem 48P

A baby elephant is stuck in a mud hole. To help pull it out, game keepers use a rope to apply a force  $\stackrel{\to }{F_A}$ , as part a of the drawing shows. By itself, however, force  $\stackrel{\to }{F_A}$  is insufficient. Therefore, two additional forces  $\stackrel{\to }{F_B}$  and  $\stackrel{\to }{F_C}$ are applied, as in part b of the drawing. Each of these additional forces has the same magnitude F. The magnitude of the resultant force acting on the elephant in part b of the drawing is k times larger than that in part a. Find the ratio  $F/F_A$  when  $k =2.00$ .