In a meter bridge experiment for measuring an unknown resistance '$S$',the null point is obtained at a distance of $30 \ cm$ from the left side,as shown at point $D$. If $R$ is $5.6 \ k\Omega$,then the value of the unknown resistance '$S$' will be $\Omega$.

In a meter bridge experiment,to minimize an error due to contact resistance,

The meter bridge shown is in a balanced position with $\frac{P}{Q} = \frac{l_{1}}{l_{2}}$. If we now interchange the positions of the galvanometer and the cell,will the bridge work? If yes,what will be the balance condition?

$(a)$ In a meter bridge,the balance point is found to be at $39.5\; cm$ from the end $A$,when the resistor $Y$ is of $12.5\; \Omega$. Determine the resistance of $X$. Why are the connections between resistors in a Wheatstone or meter bridge made of thick copper strips?
$(b)$ Determine the balance point of the bridge above if $X$ and $Y$ are interchanged.
$(c)$ What happens if the galvanometer and cell are interchanged at the balance point of the bridge? Would the galvanometer show any current?

In an experiment to determine the temperature coefficient of resistance of a conductor,a coil of wire $X$ is immersed in a liquid. It is heated by an external agent. $A$ meter bridge setup is used to determine the resistance of the coil $X$ at different temperatures. The balancing points measured at temperatures $t_1=0^{\circ} C$ and $t_2=100^{\circ} C$ are $50 \ cm$ and $60 \ cm$ respectively. If the standard resistance taken out is $S=4 \ \Omega$ in both trials,the temperature coefficient of the coil is

The resistances in the two arms of a meter bridge are $5\,\Omega$ and $R\,\Omega$,respectively. When the resistance $R$ is shunted with an equal resistance,the new balance point is at $1.6\,l_1$. The resistance $R$ is ................. $\Omega$.