A battery of emf 10 V and internal resistance 3 $\Omega$ is connected to a resistor. The current in the circuit is 0.5 A. The terminal voltage of the battery when the circuit is closed is

In a meter bridge with standard resistance of 5 $\rm \Omega$ in the left gap, the ratio of balancing lengths of the bridge wire is 2:3. The unknown resistance is

In a meter bridge, a 30 $\rm \Omega$ resistance is connected in the left gap and a pair of resistances P and Q in the right gap. Measured from the left, the balance point is 37.5 cm when P and Q are in series and 71.4 cm when they are parallel. The values of P and Q (in $\rm \Omega$) are

Shown in the figure below is a meter bridge set up with a null deflection in the galvanometer. The value of the unknown resistance R is 

A meter bridge is set up as shown, to determine an unknown resistance X using standard 10 $\rm \Omega$ resistor. The galvanometer shows null point when tapping key is at 52 cm mark. The end corrections are 1 cm and 2 cm respectively, for the ends A and B. The determined value of X is

A resistance of 5 $\rm \Omega$ is connected in the left gap of a meter bridge and 15 $\rm \Omega$ in the other gap. The position of the balancing point is