Question

A cell sends a current through a resistance `R_(1)` for time `t`, next the same cell sends current through another resistance `R_(2)` for the time `t` If the same amount of heat is developed in both the resistance then find the internal resistance of the cell

Answer 1

`[(E)/(R_(1)+r)]^(2)R_(1)=[(E)/(R_(2)+r)]^(2)R_(2)rArr r=sqrt(R_(1)R_(2))`