Shear stress, often denoted by τ (Greek: tau), is the component of stress coplanar with a material cross-section. Shear stress arises from the force vector component parallel to the cross-section of the material. Normal stress, on the other hand, arises from the force vector component perpendicular to the material cross-section on which it acts.
Shear stress arises from shear forces, which are pairs of equal and opposing forces acting on opposite sides of an object.
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