CNS $220$ Homework #$3-$ Materials

A tensile load of $50,000$ pounds is applied to a metal bar with a $0\mathrm{.}5$ inch by $0\mathrm{.}5$ inch cross

section and a length of $2$ inches. Under this load the bar elastically deforms and the bar

becomes $2\mathrm{.}007$ inches. Determine the modulus of elasticity $($E$)$ of the bar in PSI.

A cylindrical rod with a diameter of $0\mathrm{.}5$ inches and a $24-$inch length is subjected to a

tensile load. The load and elongation data is shown below. Plot the stress versus the

strain and determine the modulus of elasticity of the rod. Also, from the graph what is

the stress when the material yields.

Estimate the stress $($psi$)$ in a material that is $5$ feet long and is fully restrained at each end

against axial movement. The material is initially cast and cured at a temperature of $100$

$F$ and subsequently cools to a temperature of $0F.$ Assume that the modulus of elasticity

is $5$ million psi and the thermal coefficient is $5{10}^{-6}i\frac{n}{i}nF.$

Using material densities from the following table. What is the total weight $($in kips$)$ of a

$8$ foot tall by $25$ foot long wall that is constructed $6"$ Concrete Masonry Units with a

layer of $\frac{1}{2}"$ Gypsum board on each side.

Using material densities from the following table. What is the total weight $($in pounds$)$ of

a $6$ foot tall by $15$ foot long wall that is constructed $4"$ Lightweight Concrete Masonry

Units with a layer of $\frac{1}{2}"$ Plywood on each side.