An erect pencil on a frictionless plane

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The discussion revolves around the mechanics of a pencil released from a vertical position on a frictionless plane. Participants are exploring the appropriate principles of classical mechanics to solve for the velocity of the pencil's end when it strikes the table. Key concepts mentioned include conservation of energy and momentum, although there is uncertainty about their applicability in this scenario. The conversation also touches on the nature of forces doing work, questioning whether any non-conservative forces are involved. Overall, the focus remains on applying classical mechanics to determine the pencil's behavior as it topples.
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Homework Statement



A pencil is released from rest with θ = pi/2 and topples over. Treat the pencil as a uniform rod and find the velocity of the end A when it strikes the table if the table is frictionless.

Homework Equations



Classical Mechanics

The Attempt at a Solution



conservation of energy? not sure
conservation of momentum? doesn't seem to work
 
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zheng89120 said:

Homework Equations



Classical Mechanics

What part of Classical Mechanics do you think of?

zheng89120 said:

The Attempt at a Solution



conservation of energy? not sure

Is there any force which does work and is not conservative?

ehild
 

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