At every point of a liquid at rest,the tangential stress is zero. Explain with reason.

(N/A) Tangential stress is defined as the force acting parallel to the surface per unit area. If a liquid at rest were to experience a non-zero tangential stress,the layers of the liquid would slide over one another,causing the liquid to flow. Since the liquid is at rest,there is no relative motion between its layers. Therefore,the tangential stress at every point within a liquid at rest must be zero.