2
votes
4answers
135 views

What do you exactly mean when you say that momentum is conserved?

I am taking for granted that when we say that something is conserved it is understood 'in its full integrity'. Energy is represented by a number (of J, or other) and is usually conserved. But ...
2
votes
1answer
74 views

Conservation of linear momentum, when is it conserved?

Will Linear momentum be conserved in a non-inertial frame of reference? In other words what is the fundamental condition for linear momentum to be conserved? Also which is more fundamental- Newton's ...
2
votes
2answers
86 views

Where did the universe get its initial momentum?

If, according to Newton's third law, forces come in pairs then what about the big bang? where did the universe get that initial push/momentum?
0
votes
2answers
471 views

Simple conservation of momentum and frame of reference problem

I'm making a very simple physics engine based on momentum, and I'm solving what response to use for a collision from each involved object's frame of reference. However, something about how I'm ...
1
vote
1answer
156 views

4-momentum and an $y$ component of momentum

I have 2 coordinate systems which move along $x,x'$ axis. I have derived a Lorentz transformation for an $x$ component of momentum, which is one part of an 4-momentum vector $p_\mu$. This is my ...
1
vote
1answer
158 views

How to explain relativistic mass with 2 moving systems, but not 3?

All the visual explanations I know work in some kind of "If you are moving relative to something A, while inside A something is moving, the stuff in A has to move slower due time dilation and ...