## Solving Collisions with angles problem

First off, i'd like to note that this isn't homework, and i've seen other threads in here that deal with question/equation/problems, so I hope this isn't against the rules. I found this on a practice physics test online. I'm just using it for the benefit of my knowledge, nothing more.

I can provide the link if necessary for proof.

Heres the question I want to know how to solve:
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 Blog Entries: 27 Recognitions: Gold Member Homework Help Science Advisor Hi AceInfinity! As you know, you need to use conservation of momentum. Momentum is a vector, so this is a vector equation, which means the components of momentum in any direction are conserved. So choose a suitable direction …… what do you get?
 ohhh... I think you put me on the right track for beginning to solve this. The initial momentum was [right] in this case. Therefore the conservation of momentum is seen for that X component, I'll have to split them off into the X and Y components of momentum and look specifically at the X/horizontal component of momentum to use the conservation of momentum, if i'm not mistaken? 4.85 Cos(36o) = 3.92m/s p = mv p = (0.200kg)(3.92m/s) p = 1.2kg•m/s Solve for momentum of that object. p = mv p = (0.200kg)(3.92m/s) p = 0.784kg•m/s Momentum of the other object (puck 2) is: 1.2kg•m/s - 0.784kg•m/s = 0.416kg•m/s [Important: in the x/horizontal direction. need to solve for the angle'd direction] 0.416kg•m/s ÷ [cos(54o)] = 0.707741472...kg•m/s !!!! I think with "their" answer, they rounded a bit too early.

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## Solving Collisions with angles problem

Hi AceInfinity!
 Quote by AceInfinity Momentum of the other object (puck 2) is: 1.2kg•m/s - 0.784kg•m/s = 0.416kg•m/s [Important: in the x/horizontal direction. need to solve for the angle'd direction] 0.416kg•m/s / [cos(54o)] = 0.707741472...kg•m/s !!!!
yes that's fine

but there are quicker ways of doing it …

you could take components in the y direction or in the final direction of puck 2 …

(both are quicker because they reduce the number of terms)
try both of those

 Tags angle, collision, equation, momentum, problem