The elongation experienced by a uniform bar hanging vertically due to its own weight is equivalent to the elongation caused by which of the following weights applied at the bar's lower end?

Explanation

The total elongation of a uniform bar hanging vertically under its own weight is the same as that caused by applying a weight equal to half the bar's weight at its lower end. This is because the distributed weight along the bar produces an effect equivalent to a single concentrated load of half the total weight at the bottom.