Two thin metal strips, one of brass and the other of iron are fastened together parallel to each other. Thickness of each strip is 1 mm. If the strips are of equal length at 0°C . The inner radius of the arc formed by the bimetallic strip when heated to 80°C is (Coefficient of linear expansion of brass = 19×10–6/0C & of iron = 12 × 10–6/0C).