Two identical conducting rods are first connected independently to two vessels, one containing water at 1000C and the other containing ice at 00C. In the second case, the rods are joined end-to-end and connected to the same vessels. Let q1 and q2 gs-1 be the rate of melting of ice in two cases, respectively. The ratio of is
Initially the rods are in parallel,
…(i)
Finally when rods are in series,
…(ii)
From Eqs. (i) and (ii), we get