Chapter 3, Problem 3/021 Multistep The 180 -lb exerciser is beginning to execute some slow, steady bicep curls. As the tension $T=27 \mathrm{lb}$ is developed against an exercise machine (not shown), determine the normal reaction forces at the feet $A$ and $B$. Friction is sufficient to prevent slipping, and the exerciser maintains the position shown with center of gravity at $G$. Before answering the question parts, draw the Free-Body diagram for the exerciser. Once you have the free-body diagram, compare your diagram to the one shown in Part 1.
Part 1 Note that there are 4 unknown reaction forces in this FBD. We only have 3 equilibrium equations that can be used to solve for these unknowns, so we cannot solve for all of the forces. The problem only asks us to find the normal forces $N_{A}$ and $N_{B}$ and we can solve for these two forces. We cannot find the friction forces $F_{A}$ and $F_{B}$. Write one equlibrium equation that can be used to find the force $N_{A}$. Then solve for $N_{A}$.
Answer: $N_{A}=$ Ib

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