In the given circuit,the reading of the voltmeter connected across the $400\,\Omega$ resistor is $30\,V$. If it is connected across the $300\,\Omega$ resistor,what will be its reading in $V$?

The heat evolved or absorbed at the junction when an electric current passes through the junction of two different metals is known as which effect?

In the circuit shown,$E, F, G$,and $H$ are cells of e.m.f. $2\,V, 1\,V, 3\,V$,and $1\,V$ respectively,and their internal resistances are $2\,\Omega, 1\,\Omega, 3\,\Omega$,and $1\,\Omega$ respectively.

Two resistors with resistances $R_1$ and $R_2$ are connected in series and two capacitors with capacitances $C_1$ and $C_2$ are also connected in series. These two systems are connected to a battery of $EMF$ $\varepsilon$ as shown in the figure. The potential difference between points $a$ and $b$ is zero in the steady state if:

$A$ wire of resistance $10 \, \Omega$ is bent to form a circle. $P$ and $Q$ are points on the circumference of the circle dividing it into a quadrant and are connected to a battery of $3 \, V$ and internal resistance $1 \, \Omega$ as shown in the figure. The currents in the two parts of the circle are

The temperature of the cold junction of a thermocouple is $0\,^{\circ}C$ and the temperature of the hot junction is $T\,^{\circ}C$. The e.m.f. is $E = 16T - 0.04T^2 \, \mu\text{V}$. The temperature of inversion is ................ $^{\circ}C$.