The ends of a rod of uniform thermal conductivity are maintained at different (constant) temperatures. Afer the steady state is achieved:

Options

A. heat flows in the rod from high temperature to low temperature even if the rod has nonuniform cross sectional area.
B. temperature gradient along length is same even if the rod has non uniform cross sectional area.
C. heat current is same even if the rod has nono-uniform cross sectional area
D. if the rod has uniform cross sectional area the temperature is same at all points of the rod.

Explanation

Heat obviously flows from higher temperature in steady `implies` A is true. Temperature gradient `prop(1)/("cross section area")` in steady state `implies` B is false thermal current through each cross section area is same `impliesC` is true Temperature decreases along the length of the rod from higher temperature end to lower temperature end `impliesD` is false.