A conducting wire of length `l` and cross sectional area A is used to short the terminals of a cell having emf of `epsilon` and internal resistance `r`. The resistively, density and Molar mass of the material of the wire are `r, d and M` respectively. Calculate the average time needed for a free electron to travel from positive terminal of the cell to its negative terminal.

A conducting wire of length `l` and cross sectional area A is used to

1.	A conducting wire of length `l` and cross sectional area A is used to short the terminals of a cell having emf of `epsilon` and internal resistance `r`. The resistively, density and Molar mass of the material of the wire are `r, d and M` respectively. Calculate the average time needed for a free electron to travel from positive terminal of the cell to its negative terminal.
Answer» Correct Answer - `t=(l edN_(A)(rhol+rA))/(epsilonM)`

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