In a metre bridge experiment,the null point is obtained at $20 \,cm$ from the left end of the wire,when resistance $X$ is balanced against another resistance $Y$ $(X < Y)$. To balance a resistance $4X$ against $Y$,the new position of the null point from the same end will be: (in $\,cm$)

When the right gap of a meter bridge consists of two equal resistors in series,the balancing point is at $50 \ cm$. When one of the resistors in the right gap is removed and is connected in parallel to the resistor in the left gap,the balancing point is at: (in $cm$)

In a meter bridge (Figure), the null point is found at a distance of $33.7 \; cm$ from $A$. If now a resistance of $12 \; \Omega$ is connected in parallel with $S$, the null point occurs at $51.9 \; cm$. Determine the values of $R$ and $S$.

In the meter bridge shown,the length $AB$ for which the deflection in the galvanometer is zero will be ............. $cm$.

Two wires $A$ and $B$ of equal lengths are connected in the left and right gaps of a metre bridge. The null point is obtained at $40 \ cm$ from the left end. If the diameters of the wires $A$ and $B$ are in the ratio $3:1$,what is the ratio of the specific resistance (resistivity) of $A$ to that of $B$ (in $:$)?

In a meter bridge experiment,resistances are connected as shown in the figure. The balancing length $l_1$ is $55 \, cm$. Now,an unknown resistance $x$ is connected in series with $P$ and the new balancing length is found to be $75 \, cm$. The value of $x$ is