$2\mathrm{.}63$ Collar $A$ is connected as shown to a $50-lb$ load and can slide on a frictionless horizontal rod. Determine the magnitude of the force $P$ required to maintain the equilibrium of the coll

ar when $($a$)x=4\mathrm{.}5$ in$.,($b$)x=15in.$

Fig. P$2\mathrm{.}63$ and P$2\mathrm{.}64$