The drawing shows two thin rods, one made from aluminum [a = 23 x 10-6 (C°)-1] and the other from steel [a = 12 x 10-6 (C°)-1]. Each rod has the same length, the same initial temperature, and is attached at one end to an immovable wall, as shown. The temperatures of the rods increased, both by the same amount, until the gap between the rods is closed. Where do the rods meet when the gap is closed?

The drawing shows two thin rods, one made from aluminum [a = 23 x 10-6 (C°)-1] and the other from steel [a = 12 x 10-6 (C°)-1]. Each rod has the same length, the same initial temperature, and is attached at one end to an immovable wall, as shown. The temperatures of the rods increased, both by the same amount, until the gap between the rods is closed. Where do the rods meet when the gap is closed?