Heat is flowing through two cylindrical rods of the same material . The diameters of the rods are in the ratio 1:2 and the lengths in the ratio 2:1.If the temperature difference between the ends be the same ,then the ratio of the rate of flow if heat through them will be ?

Explanation

To solve the problem, we need to find the ratio of the rate of heat flow through two cylindrical rods with given dimensions. Let's break it down step by step.

### Step 1: Understand the given data
- The diameters of the rods are in the ratio \( d_1 : d_2 = 1 : 2 \).
- The lengths of the rods are in the ratio \( l_1 : l_2 = 2 : 1 \).

### Step 2: Relate diameter to radius
Since the radius is half of the diameter, the ratio of the radii will also be the same:
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