Shear is defined as which of the following in material behavior?

• A. a force that produces bending in a member
• B. a force that twists a member about its axis
• C. stress causing a slice or chip
• D. a force that causes buckling under compression

Answer: (C)

Shear involves forces that make adjacent layers of material slide past one another, producing distortion along a plane parallel to the force. This is the idea behind a shear stress, the component of stress that acts parallel to the cross-section. The phrase “stress causing a slice or chip” captures this sliding action, as if a thin layer could be sheared off along a plane. In contrast, bending produces normal stresses from tension and compression, twisting (torsion) twists the member about its axis, and buckling is a instability under compression. So the best description is the stress causing a slice or chip, i.e., shear.