A steel bar and an aluminum bar are bonded together to form a composite bar. Its cross section is shown above. The Young's modulus for Aluminum is 70GPa and for steel is 210GPa.
a) Pick Aluminum as the reference material, calculate modulus ratio $n_1$ and $n_2$
A
1: Steel
2:Aluminum
a)Find the location of neutral axis if there is a bending moment about the horizontal axis (bending up). $M=1000N.m$
b)Calculate the corresponding moment of inertia $I_1$.
c)Calculate the stress at the upper left corner A.
d)For a bending moment around the vertical axis (bending right) $M_y$, the neutral axis is the middle symmetric line. Calculate the corresponding moment of inertia $I_y$ and the stress at A due to $M_y=800N.m$.