11. 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) 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