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Two conductors of same length are connected in parallel as shown in figure. Their cross-sectional areas $A_1$ and $A_2$ and their resistivities are ${\rho _1}$ and  ${\rho _2}$ respectively. The equivalent resistivity of this combination is
  • A$\frac{{{\rho _1}{\rho _2}\left( {{A_1} - {A_2}} \right)}}{{{A_1}{\rho _2} + {A_2}{\rho _1}}}$
  • B$\frac{{{\rho _1}{\rho _2}\left( {{A_1} + {A_2}} \right)}}{{{A_1}{\rho _1} + {A_2}{\rho _2}}}$
  • C$\frac{{{\rho _1}{\rho _2}\left( {{A_1} - {A_2}} \right)}}{{{A_1}{\rho _1} + {A_2}{\rho _2}}}$
  • D$\frac{{{\rho _1}{\rho _2}\left( {{A_1} + {A_2}} \right)}}{{{A_1}{\rho _2} + {A_2}{\rho _1}}}$
Medium
art

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