A cell of e.m.f E is connected to a resistance R_(1) for time t and the amount of heat generated in it is H. If the resistanceR_(1) is replaced by another resistance R_(2) and is connected to the cell for the same time t, the amount of heat generated in R_(2) is 4H. Then the internal resistance of the cell is

A cell of e.m.f E is connected to a resistance R_(1) for time t and th

1.	A cell of e.m.f E is connected to a resistance R_(1) for time t and the amount of heat generated in it is H. If the resistanceR_(1) is replaced by another resistance R_(2) and is connected to the cell for the same time t, the amount of heat generated in R_(2) is 4H. Then the internal resistance of the cell is
Answer» `(2R_(1)+R_(2))/(2)` `sqrt(R_(1)R_(2))(2sqrt(R_(2))-sqrt(R_(1)))(sqrt(R_(2))-2sqrt(R_(1)))` `sqrt(R_(1)R_(2))(sqrt(R_(2))-2sqrt(R_(1)))/(2sqrt(R_(2))-sqrt(R_(1)))` `sqrt(R_(1)R_(2))(sqrt(R_(2))-sqrt(R_(1)))/(sqrt(R_(2))-sqrt(R_(1)))` ANSWER :B

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