d
\(\,{R_1} = \rho \frac{{{{l}_1}}}{{{A_1}}}\) અને  \({R_2} = \rho \frac{{{{l}_2}}}{{{A_2}}}\,\)

\( \Rightarrow \,\,\,\frac{{{R_1}}}{{{R_2}}} = \frac{{{{l}_1}}}{{{{l}_2}}}.\frac{{{A_2}}}{{{A_1}}} = \frac{{{{l}_1}}}{{{{l}_2}}}{\left( {\frac{{{r_2}}}{{{r_1}}}} \right)^2}\)

અહીં, આપ્યા મુજબ ,\(\,\frac{{{{l}_1}}}{{{{l}_2}}} = \frac{1}{2}\,\,\) અને

\(\frac{{{r_1}}}{{{r_2}}} = \frac{2}{1}\,\,\,{\text{or}}\,\,\,\frac{{{r_2}}}{{{r_1}}} = \frac{1}{2}\)

\(\,\, \Rightarrow \,\,\frac{{{R_1}}}{{{R_2}}} = \frac{1}{8}\,\)

\(\, \Rightarrow \,\) માટે ઉષ્માનો ગુણોતર  \({\text{ }}\frac{{{H_1}}}{{{H_2}}} = \frac{{{V^2}/{R_1}}}{{{V^2}/{R_2}}} = \frac{{{R_2}}}{{{R_1}}} = \frac{8}{1}\)