In the circuit shown below,the reading of the voltmeter $V$ is ........... (in $, V$)

In the circuit shown,$A$ and $V$ are an ideal ammeter and an ideal voltmeter respectively. The reading of the voltmeter will be ............... $V$.

Two wires of resistance $R_1$ and $R_2$ have temperature coefficients of resistance $\alpha_1$ and $\alpha_2$,respectively. These are joined in series. The effective temperature coefficient of resistance is

In the circuit shown,the resistance of the voltmeter is $10,000 \, \Omega$ and that of the ammeter is $20 \, \Omega$. The ammeter reading is $0.10 \, A$ and the voltmeter reading is $12 \, V$. Then $R$ is equal to ............. $\Omega$.

Find the equivalent resistance between points $A$ and $B$ in the network of resistors,each of resistance $r \Omega$.

$A$ resistance network is connected to a battery as shown in the figure below. If the internal resistance of the battery is $5 \ \Omega$,then the value of $R$ (in $\Omega$) for maximum power delivered to the network is