Two different rods `A` and `B` are kept as shown in figure . The variation of temperature of different cross sections with distance is plotted in a graph shown in figure . The ration of thermal conductivities of `A` and`B` is -

Options

A. `2`
B. `0.5`
C. `1`
D. `2//3`

Answer

B

Explanation

`because((DeltaQ)/(Deltat))_(A) = ((DeltaQ)/(Deltat))_(B)`
` therefore (K_(A)A(100-70))/(30) = (K_(B)A(70-35))/(70)`
`implies K_(A) = (K_(B))/(2) implies (K_(A))/(K_(B)) = (1)/(2)`