The ratio of thermal conductivity of two rods of different material is $5 : 4$ . The two rods of same area of cross-section and same thermal resistance will have the lengths in the ratio

Six wire each of cross-sectional area $A$ and length $l$ are combined as shown in the  figure. The thermal conductivities of copper and iron are $K_1$ and $K_2$ respectively.  The equivalent thermal resistance between points $A$ and $C$ is :-

The end $A$ of a rod $AB$ of length $1\,m$ is maintained at $80\,^oC$ and the end $B$ at $0\,^oC.$ The temperature at a distance of  $60\,\,c.m.$  from the end $A$  is……… $^oC$

The length of the two rods made up of the same metal and having the same area of cross-section are $0.6 m$ and $0.8 m$ respectively. The temperature between the ends of first rod is ${90^o}C$ and ${60^o}C$ and that for the other rod is $150^oC$ and ${110^o}C$. For which rod the rate of conduction will be greater

A metallic prong consists of $4$ rods made of the same material, cross-sections and same lengths as shown below. The three forked ends are kept at $100^{\circ} C$ and the handle end is at $0^{\circ} C$. The temperature of the junction is …………. $^{\circ} C$