Thermal conductivity of a material may be defined as the

Q. Thermal conductivity of a material may be defined as the

A.            quantity of heat flowing in one second through one cm cube of material when opposite faces ^re maintained at a temperature difference of 1°C

B.            quantity of heat flowing in one second through a slab of the material of area one cm square, thickness 1 cm when its faces differ in temperature by 1°C

C.            heat conducted in unit time across unit area through unit thickness when a temperature difference of unity is maintained between opposite faces

D.            all of the above

Answer: all of the above