Compute the normal stress

Consider the I-beam cross-section:

The table below has the geometric properties for different specifications for a steel beam:

Designation h (in) w (in) Ix (in^4) Iy (in^4)
S24 x 106 24.5 7.78 2,940 77.1
S24 x 100 24 7.425 2,390 47.7
S24 x 90 24 7.125 2,250 44.9
S24 x 80 24 7 2,100 42.2
S20 x 96 20.3 7.2 1,670 50.2
S20 x 86 20.3 7.06 1,580 46.8
S20 x 75 20 6.385 1,280 29.8
S20 x 66 20 6.255 1,190 27.7
S18 x 70 18 6.251 926 24.1
S18 x 54.7 18 6.001 804 20.8

For the beam designations indicated below, determine the maximum normal stress $\sigma_x$ assuming that the maximum moment is equal to $M_{max} = 3 \times 10^5 \rm\ lb \cdot in$.

Designation $\sigma_x$
S20 x 96
S24 x 90
S18 x 70
S18 x 54.7

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Compute the normal stress

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Started at:
2026-08-04 21:50:19 (CDT)
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{
  "sigma1": 1.8233532934131738,
  "sigma2": 1.6,
  "sigma3": 2.915766738660907,
  "sigma4": 3.3582089552238807
}
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