The reading of the voltmeter in the circuit shown is ............. $V$. (in $.25$)

Two resistances of $400 \Omega$ and $800 \Omega$ are connected in series with a $6 \text{ V}$ battery of negligible internal resistance. $A$ voltmeter of resistance $10000 \Omega$ is used to measure the potential difference across the $400 \Omega$ resistor. The error in the measurement of potential difference in volts is approximately:

Identical resistors of resistance $R$ are connected as shown in the figure. Find the equivalent resistance between $x$ and $y$.

In the circuit shown in the figure,if the potential at point $A$ is taken to be zero,the potential at point $B$ is ................ $V$.

In the ladder network shown, the current through the resistor $3\, \Omega$ is $0.25\, A$. The input voltage $V$ is equal to: (in $V$)

The storage battery of a car has an $emf$ of $12\; V$. If the internal resistance of the battery is $0.4\; \Omega,$ what is the maximum current (in $A$) that can be drawn from the battery?