1.

A cell develops the samepower across two resistance R_(1) and R_(2) separately. The internal resistance of the cell is

Answer»

Solution :Let r be the internal RESISTANCE of the cell and E its EMF. When connected across the resistance `R_(1)` in the CIRCUIT, current passing through the resistance is
`i=(E)/(R_(1)+r)""THEREFORE""P_(1)=i^(2)R_(1)=((E)/(R_(1)+rr))^(2)R_(1)`
SIMILARLY `P_(2)-((E)/(R_(2)+r))^(2)R_(2)" Given that "P_(1)=P_(2)`
Substituting the values, we get `r=sqrt(R_(1)R_(2))`


Discussion

No Comment Found

Related InterviewSolutions