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F = ma (Final Problems)
Dimensional Analysis
FMA-2008-20 · 2008 F = ma (AAPT)

2008 F = ma Exam — Question 20

20. The Young’s modulus, E, of a material measures how stiffit is; the larger the value of E, the more stiffthe material. Consider a solid, rectangular steel beam which is anchored horizontally to the wall at one end and allowed to deflect under its own weight. The beam has length L, vertical thickness h, width w, mass density ρ, and Young’s modulus E; the acceleration due to gravity is g. What is the distance through which the other end moves? (Hint: you are expected to solve this problem by eliminating implausible answers. All of the choices are dimensionally correct.)  
Source: Question 20, 2008 F = ma Exam, © 2008 American Association of Physics Teachers (AAPT) and the U.S. Physics Team. Adapted by PhysicsTrainer: reformatted into a separate question and answer choices for online multiple-choice practice; any shared setup from nearby questions is repeated here. Not affiliated with or endorsed by AAPT or the U.S. Physics Team.