The total elongation of a bar due to its self-weight is
(where w, L and E are the specific weight, length, and young’s Modulus of the bar respectively)
1
\(\rm \frac{wL^2}{E}\)
2
\(\rm \frac{w^2L}{E}\)
3
\(\rm \frac{w^2L}{2E}\)
4
\(\rm \frac{wL^2}{2E}\)