Masses of $3$ wires of same metal are in the ratio $1 : 2 : 3$ and their lengths are in the ratio $3 : 2 : 1$. The electrical resistances are in ratio
Medium
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$R \propto \frac{{{l^2}}}{m} \Rightarrow {R_1}:{R_2}:{R_3} = \frac{{l_1^2}}{{{m_1}}}:\frac{{l_2^2}}{{{m_2}}}:\frac{{l_3^2}}{{{m_3}}}$
$ \Rightarrow \,\,\,\,\,{R_1}:{R_2}:{R_3} = \frac{9}{1}:\frac{4}{2}:\frac{1}{3} = 27:6:1$.
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