
A uniform rod has a weight of and a length of . It is hinged to a wall (at the left end), and held in a horizontal position by a vertical massless string (at the right end). What is the magnitude of the torque exerted by the string about a horizontal axis which passes through the hinge and is perpendicular to the rod?




Important Questions on System of Particles and Rotational Motion
A uniform rod has a weight of and a length of . It is hinged to a wall (at the left end), and held in a horizontal position by a vertical massless string (at the right end). What is the tension in the string?

A uniform rod has a weight of and a length of . It is hinged to a wall (at the left end), and held in a horizontal position by a vertical massless string (at the right end). What is the magnitude of the hinge force?

A thin cylindrical rod of uniform mass density, rests against a smooth wall as shown in figure. Find the coefficient of friction between ground and rod (if the minimum angle that the rod can make with the horizontal is )


A rectangular plate is placed on a rough plank. Dimensions of the plank is as shown in the figure. Find the minimum acceleration with which the plank should be moved so that the rectangular plate topples (consider the friction is sufficient so the plate does not slide).

Linear mass density of a rod varies as . Among the axes shown, the moment of inertia of the rod is maximum for

Find the moment of inertia of a solid hemisphere of mass and radius about

A disc of radius is cut out from a disc of radius as shown in figure. If the remaining portion of the disc has mass M then find the moment of inertia of the disc left about an axis passing through its centre and perpendicular to its plane.
