Young's modulus when you join two different materials

[sinthreck]

Homework Statement

If you have two materials of equal length and radius and then you join them together.
Material 1 young's modulus = y1
material 2 young's modulus = y2

Homework Equations

F/a = y L_change / L_o

The Attempt at a Solution

Given they are of the same length and radius. Is the "new" youngs modulus simply their weighted average:
y_new = 0.5 * (y1 + y2)

 

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