16.76 A uniform slender rod of length Z = 900 mm and mass m = 4 kg is suspended from a hinge at C. Knowing that a horizontal force P of magnitude 75 N is applied at end B, determine (a) the distance ŕ for which the horizontal component of the reaction at C is zero, (b) the corresponding angular acceleration of the rod. _{A: A B Fig. P16.76 C G P