Reference: M62
Category: Mechanics
Purpose: Shows the forces exerted on a block resting on an inclined plane.
Description: A block, mass M, rests on a slope inclined at 30 degrees, counter-balanced by a hanging mass of 0.5M = Msin30 degrees. A triangle of forces shows that the slope must be exerting a reaction force of Mcos30 degrees = 0.866M on the block. Attach another string to M, passing over a pulley to a mass of mass 0.866M. Now the slope can be removed without disturbing the equilibrium.
