For stable structures, one of the important properties of flexibility and stiffness matrices is that the elements on the main diagonal
(i) Of a stiffness matrix must be positive
(ii) Of a stiffness matrix must be negative
(iii) Of a flexibility matrix must be positive
(iv) Of a flexibility matrix must be negative
The correct answer is
(i) and (iv)
(ii) and (iv)
(i) and (iii)
(ii) and (iii)
The stiffness element along principle diagonal of stiffness matrix is
Ans (i) and (iii)