In a meter bridge or Wheatstone bridge for the measurement of resistance,the known and the unknown resistances are interchanged. The error so removed is

The resistance of the meter bridge wire $AB$ in the given figure is $4\,\Omega$. With a cell of emf $\varepsilon_1 = 0.5\,\text{V}$ and rheostat resistance $R_{h1} = 2\,\Omega$,the null point is obtained at point $J$. When the cell is replaced by another one of emf $\varepsilon_2$,the same null point $J$ is found for $R_{h2} = 6\,\Omega$. The emf $\varepsilon_2$ is ................. $\text{V}$.

$A$ meter bridge is set up as shown to determine the end corrections at $A$ and $B$. When a resistance of $15\,\Omega$ is used in the left gap and $20\,\Omega$ in the right gap,the null point is obtained at a distance of $42\,cm$ from $A$. When these resistances are interchanged,the null point is obtained at a distance of $57\,cm$ from $A$. The values of the end corrections are:

$A$ wire of length $3 \, m$ connected in the left gap of a meter-bridge balances $8 \, \Omega$ resistance in the right gap at a point, which divides the bridge wire in the ratio $3:2$. The length of the wire corresponding to a resistance of $1 \, \Omega$ is: (in $ \, m$)

In the given arrangement of the experiment on a meter bridge,if $AD$ corresponding to the null deflection of the galvanometer is $X$,what would be its value if the radius of the wire $AB$ is doubled?

The resistances in the left and right gaps of a balanced metre bridge are $12 \Omega$ and $36 \Omega$ respectively. If the resistances are interchanged,the balance point shifts by: