Finding change in momentum in 2-dimensions.

[Oxford365]

To find the momentum change for an object in 2 dimensions do I find the initial momentum in both the x & y direction then apply the Pythagorean theorem, and then do the same for the final momentum and then find the difference between the two?

 

[Nugatory]

Momentum is a vector, so when you're looking for the change in momentum you're really looking for the difference between the initial an dthe final momentum vectors. Google for "vector subtraction Cartesian coordinates" and you'll find plenty of examples.

 

[Khashishi]

If you just want the magnitude,
$\Delta p = \sqrt{(p_{1x} - p_{2x})^2 + (p_{1y}-p_{2y})^2}$