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 ............. $\Omega$.

In the circuit shown below, a student performing Ohm's law experiment accidentally connects the voltmeter and the ammeter as shown. The reading in the voltmeter will be close to .......... $V$.

$P$ and $Q$ are two identical wires of resistance $2000\, \Omega$ each, and $M$ is the midpoint of $PQ$. A voltmeter of resistance $1000\, \Omega$ is connected between $P$ and $M$. When a potential difference of $150\, V$ is applied across $PQ$, the reading of the voltmeter will be ............. $V$.

In the circuit given, $E = 6.0 \, V$, $R_1 = 100 \, \Omega$, $R_2 = R_3 = 50 \, \Omega$, and $R_4 = 75 \, \Omega$. The equivalent resistance of the circuit, in $\Omega$, is:

Three equal resistors connected in series across a source of $e.m.f.$ together dissipate $10 \ W$. If the same resistors are connected in parallel across the same $e.m.f.$,then the power dissipated will be .............. $W$.

In the circuit shown in the figure, the heat produced in the $5\, \Omega$ resistance is $10\, \text{cal/sec}$. The heat produced in the $4\, \Omega$ resistance is ................ $\text{cal/sec}$.