The lever rule is an analytical tool used to determine which of the following in a simple beam with or without a loaded overhang?

• A. Moment distribution in continuous beams
• B. Reactions at the supports
• C. Shear force distribution along the beam
• D. Deflection at midspan

Answer: (B)

The lever rule uses equilibrium of moments to find the support reactions in a beam, including when there is an overhang. In a simple beam with two supports, the vertical reactions must balance both the vertical loads and the moments those loads create about the supports. By taking moments about one support, the reaction at the other support times the span equals the sum of each load times its distance from that same support. Solve for that reaction, then use the total vertical load to get the remaining reaction. The resulting distribution reflects how the loads’ lever arms influence how much each support must carry.

This approach focuses on reactions at the supports and does not directly determine internal moment distribution, shear along the beam, or deflection at midspan.