A uniform beam 4.0 m long and of mass 20 kg lies horizontally
PHYSICS · Multi-part · CBSE · Physics · System of Particles and Rotational Motion · System of Particles and Rotational Motion
Problem
A uniform beam 4.0 m long and of mass 20 kg lies horizontally. One end of the beam (call this the left end) rests on a small support stand that can exert only an upward force. A crate of mass 50 kg is placed at the right end of the beam. The system remains at rest on a level floor. Throughout the problem, neglect friction between the beam and the floor.
(a) Choose an appropriate point about which to calculate torques and write the rotational equilibrium condition for the beam–crate system.
(b) Determine the distance from the left end of the beam at which the support stand must be placed so that the beam remains perfectly horizontal.
(c) Calculate the magnitude of the upward force exerted by the support stand on the beam.