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# The breaking stress of aluminium is $7\times 10^7N/m^2$.Find the maximum length of wire that can be hang with out breaking if density of aluminium is $3\times 10^3Kgm^{-3}$

$\begin{array}{1 1}(A)\;2.83\times 10^3m\\(B)\;2.38\times 10^3m\\(C)\;5.83\times 10^3m\\(D)\;2.67\times 10^3m\end{array}$

The maximum stress is a highest point of wire which is equal to $Sgl_{max}$
Given $S=3\times 10^3kg/m^3$
$Stress_{max}=70\times 10^7$
$l_{max}=\large\frac{7.0\times 10^7}{3\times 10^3\times 9.8}$
$\Rightarrow 2.38\times 10^3m$
Hence (B) is the correct answer.