$AB$ is a wire of uniform resistance. The galvanometer $G$ shows no current when the length $AC = 20\,cm$ and $CB = 80\,cm$. The resistance $R$ is equal to .............. $\Omega $

In a Wheatstone's bridge,three resistances $P, Q$ and $R$ are connected in the three arms,and the fourth arm is formed by two resistances $S_1$ and $S_2$ connected in parallel. The condition for the bridge to be balanced will be

$A$ Wheatstone bridge is initially at room temperature and all arms of the bridge have the same value of resistance $(R_1=R_2=R_3=R_4=R)$. When $R_3$ is heated to some temperature,its resistance value increases by $10 \%$. The potential difference $(V_a - V_b)$ (after $R_3$ is heated) is . . . . . . $V$. Given the total voltage is $40 \text{ V}$.

In the given circuit, what is the potential difference between $X$ and $Y$ in $V$?

As shown in the figure,for the balanced condition of the Wheatstone bridge,the value of $n$ is . . . . . .

The potential difference $(V_{A}-V_{B})$ between the points $A$ and $B$ in the given part of the circuit is