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Which beam is stronger?

A) a beam with cross-section dimensions 4"x10" and 8' long

B) a beam with cross-section dimensions 4"x12" and 12' long

Both beams are same material and are both simply supported at the ends. Same load type (either concentrated or distributed doesn't really matter) and same load location.

Here are my thoughts:

Moment of inertia for beams: A: 333.33 in^4; B: 576 in^4

Lengths of beams: A: 96 in; B: 144 in

Using the equation for a concentrated load at the center: P = (deflection*48*E*I)/(L^3)

The deflection of beam A is about half the deflection of B. Does this mean A is stronger with the given loads?

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# Which beam is stronger?

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