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physicsss
Oct7-04, 08:04 PM
A 3.0 m long steel chain is stretched out along the top level of a horizontal scaffold at a construction site, in such a way that 2 m of the chain remains on the top level and 1.0 m hangs vertically. At this point, the force on the hanging segment is sufficient to pull the entire chain over the edge. Once the chain is moving, the kinetic friction is so small that it can be neglected. How much work is performed on the chain by the force of gravity as the chain falls from the point where 1 m remains on the scaffold to the point where the entire chain has left the scaffold? (Assume that the chain has a linear weight density of 60 N/m.)

Is it W=60*9.8(3-2)?

Sirus
Oct7-04, 10:05 PM
What is the chain's displacement?

Sirus
Oct7-04, 10:14 PM
Also, think about the linear weight density, units in particular. What is the gravitational force acting on the chain?

physicsss
Oct7-04, 10:32 PM
So the answer is just 35 J?

Doc Al
Oct8-04, 08:21 AM
How much work is performed on the chain by the force of gravity as the chain falls from the point where 1 m remains on the scaffold to the point where the entire chain has left the scaffold?
Consider the change in gravitational potential energy.