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## Homework Statement

A hanging wire made of an alloy of titanium with diameter 0.15 cm is initially 2.8 m long. When a 109 kg mass is hung from it, the wire stretches an amount 1.41 cm. A mole of titanium has a mass of 48 grams, and its density is 4.54 g/cm^3.

Based on these experimental measurements, what is Young's modulus for this alloy of titanium?

From the mass of one mole and the density you can find the length of the interatomic bond (diameter of one atom). This is 2.60E-10 m for titanium. What is the k{s,i}?

## Homework Equations

k{s,i}: stiffness of an interatomic bond in a solid.

Y= stress/strain = (tension force/cross section area)/(change of Length/Length)

Y = ((k{s,i}*s)/diameter^2)/(s/diameter) = k{s,i}/diameter

## The Attempt at a Solution

stress = changeL/L = .0141m/2.8m = 5.035714E-3

strain = F{T}/A = 9.81*mass / pi*(7.5E-4)^2 = 5.532E11

4.5g/cm^3 = 4.5E3kg/m^3

(mass = Density*length^3 = 4.5E3kg/m^3*(2.8 m)^3 = 99662.08)

stress/strain = Y = 9.10195E-15

I'm pretty sure that's the wrong answer.