In a meter bridge,two gaps in the metallic strip are connected by $3 \Omega$ and $9 \Omega$ resistors. What should be the value of the shunt that needs to be added in parallel to the $9 \Omega$ resistor to shift the balancing point by $25 \text{ cm}$ (in $\Omega$)?

When a metal conductor connected to the left gap of a meter bridge is heated,the balancing point

$STATEMENT-1$: In a Meter Bridge experiment,a null point for an unknown resistance is measured. Now,the unknown resistance is placed inside an enclosure maintained at a higher temperature. The null point can be obtained at the same point as before by decreasing the value of the standard resistance.
$STATEMENT-2$: The resistance of a metal increases with an increase in temperature.

The experimental setup of a meter bridge is shown in the figure. If the null deflection point of the galvanometer is at distance $x$ from end $A$,what will be the new null point if the radius of the wire $AB$ is doubled?

In a meter bridge experiment,the null point is obtained at $20 \ cm$ from one end of the wire when resistance $X$ is balanced against resistance $Y$. If $X < Y$,then the distance of the new null point from the same end when a resistance of $4X$ is balanced against $Y$ will be ............ $cm$.

In a meter bridge experiment,resistances are connected as shown in the figure. Initially,resistance $P = 4\,\Omega$ and the null point $N$ is at $60\,cm$ from $A$. Now,an unknown resistance $R$ is connected in series to $P$,and the new position of the null point is at $80\,cm$ from $A$. The value of unknown resistance $R$ is