A battery of emf `E` and internal resistance `r` is connected to a resistor of restance `r_(1)` and Q Joules of heat is produced in a certain time `t`. When te same battery is connected to another resistor of resistance `r_(2)` the same quantity of heat is produced in the same time `t`. Then the value of `r` isA. `(r_(1)^(2))/(r_(2))`B. `(r_(2)^(2))/(r_(1))`C. `(1)/(2)(r_(1)+r_(2))`D. `sqrt(r_(1)r_(2))`

A battery of emf `E` and internal resistance `r` is connected to a res

1.	A battery of emf `E` and internal resistance `r` is connected to a resistor of restance `r_(1)` and Q Joules of heat is produced in a certain time `t`. When te same battery is connected to another resistor of resistance `r_(2)` the same quantity of heat is produced in the same time `t`. Then the value of `r` isA. `(r_(1)^(2))/(r_(2))`B. `(r_(2)^(2))/(r_(1))`C. `(1)/(2)(r_(1)+r_(2))`D. `sqrt(r_(1)r_(2))`
Answer» Correct Answer - D `Q=(V^(2))/(r_(1))=(E^(2)r_(1))/((r+r_(1))^(2))` `Q=(V^(2))/(r_(2))=(E^(2)r_(2))/((r+r_(2))^(2))`

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