A prismatic cantilever prestressed concrete beam of span length, \( L = 1.5 \, \text{m} \), has one straight tendon placed in the cross-section as shown in the following figure (not to scale). The total prestressing force of 50 kN in the tendon is applied at \( d_c = 50 \, \text{mm} \) from the top in the cross-section of width, \( b = 200 \, \text{mm} \) and depth, \( d = 300 \, \text{mm.}\)
