\(\therefore \,\,F = Y\pi {r^2}\frac{l}{L}\)
\(\frac{{{F_A}}}{{{F_B}}} = \frac{{{Y_A}}}{{{Y_B}}}{\left( {\frac{{{r_A}}}{{{r_B}}}} \right)^2}\left( {\frac{{{l_A}}}{{{l_B}}}} \right)\,\left( {\frac{{{L_B}}}{{{L_A}}}} \right)\)
\( = 1 \times {\left( {\frac{2}{1}} \right)^2} \times \left( 1 \right) \times \left( {\frac{2}{1}} \right) = 8\)
[તારનો આડઇેદનું ક્ષેત્રણ $=0.005 \mathrm{~cm}^2 \gamma=2 \times 10^{11} \mathrm{Nm}^{-2}$ અને $\mathrm{g}=10 \mathrm{~ms}^{-2}$ ]