Two identical conducting rods are first connected independently to two vessels, one containing water at `100^@C` and the other containing ice at `0^@C`. In the second case, the rods are joined end to end and connected to the same vessels. Let `q_1 and q_2` gram per second be the rate of melting of ice in the two cases respectively. The ratio `q_1/q_2` is
(a) `1/2` (b)`2/1` (c)`4/1` (d)`1/4`

Options

A. `(1)/(2)`
B. `(2)/(1)`
C. `(4)/(1)`
D. `(1)/(4)`

Answer

D

Explanation

`q_(1)L = (k(2A)(T_(1)- T_(2)))/(l)`
`implies q_(2)L = (kA(T_(1) - T_(2)))/(2l) implies (q_(2))/(q_(1)) = (1)/(4)`