KVPY2018PhysicsThermal Properties of Matter
In steady state heat conduction, the equations that determine the heat current j r [heat flowing per unit time per unit area] and temperature T r in space are exactly the same as those governing the electric field E r and electrostatic potential V r with the equivalence given in the table below. Heat flow Electrostatics T r V r j r E r We exploit this equivalence to predict the rate Q of total heat flowing by conduct
Options
- A2
- B1
- C- 1
- D- 2
Correct answer
A. 2
Step-by-step solution
Temperature difference causes heat to flow. So, potential difference is equivalent to temperature difference. As, d V d R = - E = - k Q R 2 We can write for heat flux, d T d R = - k Q R 2 Here, Q = heat transferred. ⇒ Q ∝ R 2 when d T δ R = constant. ∴ n = 2