$|A|$

$($B$)$

The cantilever shown in Figure A has a square crosssection with a side length of $d=4mm($figure $B).$ If the density and the yield strength of the material that the bar is made of are $=5600kg{m}^{-3},$ and ${}_{\text{y}\text{i}\text{e}\text{l}\text{d}}=420$ MPa, respectively, what is the maximum length, $L,$ of the bar that can be used in a cantilever configuration without showing any plastic deformation? You should take the gravitational acceleration as $g=9\mathrm{.}81m{s}^{-2}.$

Give your answer in meters to $3$ significant figures.

Maximum length: $L=$

m