An accumulator of emf `2 V` and negligible internal resistance is connected across a uniform wire of length 10 m and resistance `30 Omega` The appropriate terminals of a cell of emf `1.5 V` and internal resistance `1 Omega` is connected to one end of the wire and the other terminal of the cell is connected through a sensitive galvanometer to a slider on the wire. What is the length of the wire that will be required to produce zero deflection of the galvanometer? How will the balancing length change?
(a) When a coil of resistance `5Omega` is placed in series with the accumulator.
(b) The cell of `1.5 V` is shunted with `5 Omega` resistor?

Explanation

`6.67Omega`