Conservation of Momentum of two carts Problem

AI Thread Summary
The problem involves two carts, each with a mass of 1kg, moving towards each other at different speeds, resulting in a momentum calculation. The momentum vectors for the carts are calculated as [4, 0, 0] kg·m/s for the first cart and [-2, 0, 0] kg·m/s for the second. The total momentum before the collision is found to be [2, 0, 0] kg·m/s. Assuming momentum conservation, if the first cart comes to rest after the collision, the final velocity of the second cart is calculated to be [2, 0, 0] m/s. The discussion also clarifies the correct notation for column vectors in this context.
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Homework Statement



Two carts, each with a mass of 1kg, are moving along a track towards one another. One cart is moving to the right at 4m/s and the other is moving to the left at 2m/s. Write down the momentum vector for each cart in column vector notation. Add these together to get the total momentum vector for the system of carts. Assuming this is conserved in the impending collision, and that the cart initially moving to the right ends up at rest after the collision, find the final velocity of the second cart in column vector notation.

Homework Equations




The Attempt at a Solution



ma = 1kg
vaix = 4m/s
vafx = 0 m/s

mb = 1kg
vbix = -2m/s
vbfx = ?

ma*vai + mb*vbix = ma*vafx + mb*vbfx

(1 kg)([4,0,0]m/s) + (1kg)([-2,0,0]m/s) = (1kg)([0,0,0]m/s) + (1kg)(vbfx)

vbfx = [2,0,0] m/s (is this correct column vector notation?)
 
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That's a row-vector, actually. Column vectors are either witten as the transpose of a row-vector
[2,0,0]T, which is convenient if you want it to fit in a line. Or it can also written as

\left[\begin{array}{cc}2\\0\\0\end{array}\right]
 
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