Indeterminate Beam Problem- Mechanics Of Solids A beam ABC rests on supports A and B and is supported by a cable at C that has a length h = 2(m). The beam ABC with lengths L = 2(m) (shown in Figure 3 below) supports a uniform load q = 20 (kN/m) that acts over the entire distance \' Solution a) moment of inertia of beam = 1/12 *d 4 = 520833.33 mm 4 E= 70kN/mm 2 EI = 520833.33 *70= 3.65*10 7 kN-mm 2 b) axeal rigidity of cable EA= 210 *3.14*5 2 = 16493 .36 kN C) let tension in cable C = T then balance moment about point A T*4+ R B *2 = 20*4*2 = 160 OR R B +2T = 80 ----------1 BALANCE MOMENT ABOUT POINT C R A *2 - 20*2*1 = T*2- 20*2*1 OR R A = T -------------- 2 R A + R B + T= 20*4 = 80 D) deflection at C = T*2/(EA) .