Speed of chain with few variables

Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
2 replies · 1K views
BearMan
Messages
3
Reaction score
0
I have no idea how to solve this. All i can think of is that you need mass to solve the problem.

Homework Statement


A chain is lying flat on a table. It has no friction against the flat surface. You pull the chain to the edge of the table so that it from a resting state starts to slide down from the table. The chain is 30 cm long. Calculate the chains velocity when the chain has left the table.


Homework Equations


v^2*m*0.5 = Ek
 
Physics news on Phys.org
BearMan said:
I have no idea how to solve this. All i can think of is that you need mass to solve the problem.

Homework Statement


A chain is lying flat on a table. It has no friction against the flat surface. You pull the chain to the edge of the table so that it from a resting state starts to slide down from the table. The chain is 30 cm long. Calculate the chains velocity when the chain has left the table.


Homework Equations


v^2*m*0.5 = Ek

As usual with these types of questions, start by drawing the free body diagram (FBD) for the setup. In this case, I would draw 3 FBDs -- one for the case when the chain is just barely starting to fall, one for mid-fall, and one for when the full chain has just left the table.
 
I would also think about conservation of energy for this one, to avoid some difficult differential equations. You're going to have potential energy transferred to kinetic as the chain falls, so the solution will involve thinking about how much potential energy is going to be lost by the chain once it has left the table.
 
  • Like
Likes   Reactions: 1 person