(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The well-known civil engineering firm of Rivers, Rhodes, and Waters is designing a walkway that is to be suspended by means of four steel rods of diameter 2.0 cm and length 2.80 m. The stretch of the rods is not to exceed 0.46 cm under any circumstances. What is the maximum additional mass that the 1030 kg walkway can carry to meet the design specifications? Assume that the load is uniformly distributed over the walkway so that each rod carries an equal share of the load.

2. Relevant equations

Young's Modulus for steel (E) = 2 x 10[tex]^{11}[/tex]

E = (F / A) / ([tex]\Delta[/tex]l / l)

F = mg

A = [tex]\pi[/tex]r[tex]^{2}[/tex]

3. The attempt at a solution

A = 4 [tex]\pi[/tex]r[tex]^{2}[/tex]

A = 4 [tex]\pi[/tex] (.01)[tex]^{2}[/tex]

A = .00125m[tex]^{2}[/tex]

F = mg

F = 1030(9.8)

F = 10094N

l = 2.8m, [tex]\Delta[/tex]l = .0046m

E = (10094 / .00125) / (.0046 / 2.8) = 4.915 x 10[tex]^{11}[/tex] N/m[tex]^{2}[/tex]

(2 x 10[tex]^{11}[/tex] - 4.915 x 10[tex]^{11}[/tex]) = 1.951 x 10[tex]^{11}[/tex]

1.951 x 10[tex]^{11}[/tex] = (F / .00125) / (.0046 / 2.8)

F = 400620.285 - 10094 = 390526.285N

m = 39849.621kg

The answer above was wrong, any help will be appreciated!

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# Homework Help: Frustrating Problem

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