Re: are normal reaction and tension conservative ?

[Chetan <chetanreddy@ETH.NET>]

> How can somebody answer your question without
> knowing what is meant by "it"? Where is the question
> which you are trying to answer?
> From: "Ludwik Kowalski" <kowalskiL@MAIL.MONTCLAIR.EDU>



I am  sorry i couldn't convey myself properly.
my "it" was reference to the subject line.



Consider the case of a plank (with a block on it ) at rest on the floor.
the work done by normal reaction is zero.

Now imagine  a man pushes the plank upward with an acceleration.
Now the work done by normal reaction is nonzero.

can normal reaction in the second case be considered non conservative.


A similar situation is the case of a body at the lower end of a rope being
pulled vertically upward by a man moving the upper end. could we label
tension as non conservative?






> Chetan wrote:
>
> > I think it depends on what forces are causing the normal reaction and
> > tension(like when two masses are hanging on the opposite sides of a
pulley
> > then the tension in th rope is due to gravity which is a conservative
force
> > and so the tension is conservative).
> >
> > Is this right?
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