A wall consists of alternating blocks withlength 'd' and coefficient of thermal conductivity `k_(1)` and `k_(2)`. The cross sectional area of the blocks are the same. The equivalent coefficient of thermal conductivity of the wall between left and right is:-

A wall consists of alternating blocks of length 'd' and coefficient of thermal conductivity k_(1) and k_(2) respectively as shown in figure. The cross sectional area of the blocks are the same. The equivalent coefficient of thermal conductivity of the wall between left and right is . . . . .

Two rods of length l_(1) and l_(2) and coefficients of thermal conductivities k_(1) and K_(2) are kept touching each other. Both have the same area of cross-section. The equivalent of thermal conductivity is

Two rods of length d_(1) and d_(2) and coefficients of thermal conductivites K_(1) and K_(2) are kept touching each other. Both have the same area of cross-section. The equivalent thermal conductivity.

Two rods of length d_(1) and d_(2) and coefficients of thermal conductivites K_(1) and K_(2) are kept touching each other. Both have the same area of cross-section. The equivalent thermal conductivity.

A metal rod of area of cross section A has length L and coefficient of thermal conductivity K the thermal resistance of the rod is .

Two rods of length l and 2l thermal conductivities 2K and K are connected end to end. If cross sectional areas of two rods are eual, then equivalent thermal conductivity of the system is .