2D Momentum and Collisions Lab Help Grade 12

AI Thread Summary
The discussion revolves around solving for an unknown mass in a completely inelastic collision experiment involving two masses. The known mass is 0.583 kg, and the user is attempting to apply the momentum conservation equation, m1v1 + m2v2 = m3v3, where m3 is the total mass (m1 + m2) and v3 is the combined velocity. The user is confused about rearranging the equation to isolate m2, as they encounter cancellation issues when moving terms. Clarification was provided that there should be no cancellation, and the user expressed gratitude after resolving the confusion. The focus remains on correctly applying momentum conservation principles to find the unknown mass.
Ranjan1995
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Homework Statement



For a lab, I have performed a completely inelastic collision using 2 masses. One mass is 0.583 kg, and the other is the unknown we have to find. Using an air table, I was given the dots to show the movements of the objects as they intersect and them move together. I have broken them into components and solved for the velocity and the momentum for each. Well, that's where the problem is:

Momentum of the known mass:

m1v1 = p1
m1x(v1x) = p1x
m1y(v1y) = p1y

Same thing for the second mass, except it is m2, an unknown.

When they move together, I know the mass will be the total (m1 + m2, which i state as m3) and the velocity will also be something else, v3.

Now, the problem:

I am trying to do m1v1 + m2v2 = m3v3 to find the unknown mass Question is, how would i rearrange the equation to find this m2.


Homework Equations



mv = p
1/2mv^2

The Attempt at a Solution



I am just trying with the 'x' component for the example:

m1 = 0.583 kg
v1x = 0.18 m/s [E]

m2 = unknown
v2x = 0.29 m/s [W]

m3 = m1 + m2
v3x = 0.05 m/s [W]

m1v1 + m2v2 = m3v3

How can i find this mass, it cancels out the moment I bring one of the m2's to the other side , I am I making some mistake here? I know it may not seem like I did any work, but I have pages of work getting to this part haha.
 
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what else could you call m3?
 
m3 is (m1 + m2)
 
i think you should show your work so far. there is no reason anything should cancel out.
 
I got it, thanks.
 
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