The two ends of a uniform rod of thermal conductivity k are maintained at different but constant temperatures. The temperature gradientat any point on the rod is `(d theta)/(dl)`(equal to the difference in temperature per unit length). The heat flow per unit time per unit cross-section of the rod is `l` then which of the following statements is/are correct:

Options

A. `(d theta)/(dl)` is the same for all points on the rod.
B. l will decrease as we move from higher to lower temperature.
C. `l=k. (d theta)/(dl)`
D. All the above options are incorrect.

Answer

A, C, D