In the given circuit,if the measuring instruments are ideal,then the reading of ammeter $A_1$ is:

An electric bulb rated $500 \, W$ at $100 \, V$ is used in a circuit having a $200 \, V$ supply. Calculate the resistance $R$ to be connected in series with the bulb so that the power delivered by the bulb is $500 \, W$. (in $\Omega$)

In steady state, the potential difference across the capacitor is $10\, V$. Each resistance is of $3\, \Omega$. The cell is ideal. The $emf$ of the cell is ............. $V$.

Which of the four resistances $P, Q, R$ and $S$ generate the greatest amount of heat when a current flows from $A$ to $B$?

Five identical resistors, each of resistance $R = 1500 \Omega$, are connected to a $300 \text{ V}$ battery as shown in the circuit. The reading of the ideal ammeter $A$ is: (in $\text{ A}$)

Suppose there is a circuit consisting of only resistances and batteries. Suppose one is to double (or increase it to $n$-times) all voltages and all resistances. Show that currents are unaltered.