When a current passes through a wire whose different parts are maintained at different temperatures,the evolution or absorption of heat all along the length of the wire is known as:

Two rods of copper $(Cu)$ and iron $(Fe)$ with the same cross-sectional area are joined at $S$ and a steady current $I$ flows through the rods as shown in the figure. Choose the most appropriate representation of charges accumulated near the junction $S$.

In the circuit of the adjoining figure,the current through the $12 \ \Omega$ resistor will be ................ $A$.

The resistance of the filament of a lamp increases with the increase in temperature. $A$ lamp rated $100\, W, 220\, V$ is connected across a $220\, V$ power supply. If the voltage drops by $10\%$,then the power of the lamp will be:

An electric kettle has two coils. When one coil is switched on,the tea gets heated in $10 \, \text{min}$. When the other coil is switched on,the same amount of tea gets heated in $40 \, \text{min}$. If both coils are connected in parallel,how long will it take to heat the same amount of tea (in $, \text{min}$)?

The cold junction of a thermocouple is at $10\,^{\circ}\text{C}$. When the temperature of the hot junction is $530\,^{\circ}\text{C}$,no thermo-emf is produced. What is the neutral temperature in $^{\circ}\text{C}$?