(Solved): The 612-in. timber beam has been strengthened by bolting to it the steel reinforcement shown. Th ...

The $$6\times 12$$-in. timber beam has been strengthened by bolting to it the steel reinforcement shown. The modulus of elasticity for wood is $$1.8\times 10^6\mathrm{psi}$$ and for steel is $$29\times 10^6$$ psi. Knowing that the beam is bent about a horizontal axis by a couple of moment $$M=458$$ kip.in., determine the radius of curvature caused by the couple. The radius of curvature caused by the couple is $$\mathrm{ft}$$.