Correct Answer - Option 2 : Current
Explanation:
Heat flow has an analogy in the flow of electricity.
Ohm’s law states that the current ‘I’ flowing through a wire is equal to the voltage potential (E1 – E2) divided by the electrical resistance Re.
\(I = \frac{{{E_1} - {E_2}}}{{{R_e}}}\)
Since the temperature difference and heat flux in conduction are similar to the potential difference and electrical current respectively, the rate of heat conduction through the wall can be written as
\(Q = \frac{{{T_1} - {T_2}}}{{L/kA}} = \frac{{{T_1} - {T_2}}}{{{R_{th}}}}\)
Where Rth = \(\frac{{L}}{{kA}}\) is the conductive thermal resistance to heat flow offered by the wall.
Fourier's law of heat conduction is analogous to Ohm's law for electrical circuits. In the analogy:
- the heat flow (Q) corresponds to the electrical current (I)
- the thermal resistance to the electrical resistance
- temperature (T) to the electrical voltage (V)
- thermal conductivity to the electrical conductivity
- heat capacity to the capacitance