## Question

Two different metal rods of the same length have their ends kept at the same temperatures and with . If *A* and *B *are their cross-sectional areas and *k*_{1} and *k*_{2} their thermal conductivities, the rate of flow of heat in the two rods will be the same if

### Solution

Rate of flow is

Since and *l* are the same for the two rods, the rate of flow *Q/t*will be the same if the product *kA* is the same if the product *kA* is the same for the two rods, i.e. if

or

#### SIMILAR QUESTIONS

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