The angle of inclination of the plane, at which the body begins to move down the plane is called

A. μ₁ = μsinβ B. μ₁ = μcosβ C. $${\mu _1} = \frac{\mu }{{\sin \beta }}$$ D. $${\mu _1} = \frac{\mu }{{\cos \beta }}$$

A. Self-closed B. Force-closed C. Friction closed D. None of these

A. Sliding B. Turning C. Rolling D. Screw

A. None of the links is fixed B. One of the links is fixed C. Two of the links are fixed D. None of these