Question

Causider a hoist that i on a beum, as shown in Fieure I below Figure 1: IHoist on a beam. The hoist Q moves on a horizontal beam; let a denote the distance along the beam The hoist is externally driven to follow a trajectory such that its position at time t obeys r(e)-f), where f(e) is a function that will be specified when needed. The load is modeled as a point P of mass mp which hangs from the hoist on a chain of length e the chain is free to rotate about Q in the plane of the page Note: Unless otherwise specified, assume that the chain is taut (ie., that the chain is pulled tight), and neglect the mass of the chain. 1. How many degrees of freedom does this system have? (5) Answer: (Hint: the distance controlled.) represents a degree of freedom, even though it is externally 2. Draw the free body diagram of the mass P. (10)

Answer 1

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