Re: The opposing rockets and the box

Greg Neill wrote:
"Spaceman" <spaceman@xxxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
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Greg Neill wrote:
"Spaceman" <spaceman@xxxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
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Greg Neill wrote:
"Spaceman" <spaceman@xxxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
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You removed the M for no reason at all.
You made it basically dissapear from the problem
without even knowing where you went wrong.
For some stupid ass reason you made m*v
hit a larger mass and still stay as m*v again even though
it combined with a larger mass.
Are you really that dense?

You have m*v = v*m/(M + m)
You are truly lost.

That is not what I wrote. I wrote v2 = v*m/(M + m).
That's the velocity of the combined masses following
the collision.

And then you said that was equal to m*v all over again.

No, I said that the momentum was conserved, and that
the momentum after the collision and the bodies are
stuck together is given by v2*(M + m).

I then plugged in the expression for the velocity v2
into that.

No you did not.

Sorry, but I did.

Also, I corrected myself with regards the above paragraph in
a separate post. I meant to say that the *velocity* after the
collision was given by v2 = v*m/(M + m). The momentum is
thus (M + m) * v2 = (M + m) * v*m/(M + m) = m*v. That is,
momentum is conserved (the same before and after the
collision).

See, you did it again and can't even tell.
You started with the small mass moving (m*v)
And then you played all around and came up yet again
with (m*v) all over again Greg.
You might as well ignore the larger mass completely.
You would get the same answer of m*v.
Sheesh


--
James M Driscoll Jr
Spaceman


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