A Simply Supported Wood Beam (L = 5 M) with Rectangular

question 4

Multiple Choice

A simply supported wood beam (L = 5 m) with rectangular cross section (b = 200 mm, h = 280 mm) car- ries uniform load q = 6.5 kN/m includes the weight of the beam. The maximum flexural stress is approximately:

• A) 8.7 MPa
• B) 10.1 MPa
• C) 11.4 MPa
• D) 14.3 MPa

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Definitions:

Phosphate Group

A functional group consisting of a phosphorus atom bonded to four oxygen atoms, crucial in the structure of DNA and energy transfer.

Antioxidant Molecules

Compounds that prevent oxidation, a chemical reaction that can produce free radicals and thus damage cells.

Free Radicals

Highly reactive molecules with unpaired electrons that can cause damage to cells and DNA, playing a role in aging and various diseases.

Aerobic Respiration

Oxygen-requiring cellular respiration; breaks down organic molecules (particularly glucose) and produces ATP, carbon dioxide, and water. Includes glycolysis, acetyl–CoA formation, the Krebs cycle, and electron transfer phosphorylation.