Draw a schematic diagram of a circuit consisting of a cell of $1.5 \, V$, a $10 \, \Omega$ resistor, a $15 \, \Omega$ resistor, and a plug key, all connected in series.

Draw a labelled circuit diagram showing three resistors $R_{1}, R_{2}$ and $R_{3}$ connected in series with a battery $(E)$,a rheostat $(Rh)$,a plug key $(K)$ and an ammeter $(A)$ using standard circuit symbols. Use this circuit to show that the same current flows through every part of the circuit. List two precautions you would observe while performing the experiment.

In the given circuit,calculate $(i)$ total resistance of the circuit,and (ii) current shown by the ammeter.

Should the resistance of an ammeter be low or high? Give reason.

An electron in a metal is free to move anywhere but cannot leave the metal.

Define one watt.