# What can I consider 'fundamental definitions'?

1. Nov 22, 2013

### oddjobmj

What are considered fundamental definitions? For context, a question was posed where the prof. provided parametric equations for the motion of a satellite in orbit and said that we can use the provided equations, fundamental definitions, and no other equations to solve the problems.

What does that mean?

I thought I had an idea of what that meant but a part of the question asks for us to solve for momentum but none of the parametric equations contain momentum explicitly which means we have to use -some other relationship- to introduce momentum to the system of equations. So, I thought I would pose that question here and see what you guys think.

Last edited: Nov 22, 2013
2. Nov 22, 2013

### HallsofIvy

Staff Emeritus
Well, if the problem asks for "momentum", the definition of momentum would be pretty fundamental wouldn't it?

3. Nov 22, 2013

### oddjobmj

Absolutely, but that doesn't help me work out what relationships are fundamental. I say this because if we suppose that all relationship that are necessary to solve the problem are fundamental we get nowhere because even then I can't know which are fundamental until I know how to solve the problem. Is it truly this arbitrary or is there some sort of distinction that I can use to at least make a reasonable argument that something is fundamental?

4. Nov 22, 2013

### Staff: Mentor

I'd ask your professor exactly what they mean by "fundamental definitions". Our opinions here could be entirely different from what he actually meant.