# Real life uses for math for the layman/undergraduate?

1. Aug 25, 2013

### Keith Young

Hey guys, first post here.

I am making a list of applied math examples and I was wondering what uses you guys know. For example I recall in Numerical we learned the Shooting Method. It didn't make any sense to me until I realized it could be used in Beam Deflection.

Applied Math Examples List - Methods - Real World Uses

I tend to write more about Motorsports Engineering applications, but I'll take just about any application you throw at me as long as I can understand it enough to write about it.

I hope this can help as many people as possible, and one day I hope to have that list complete.

Thanks for the help!

2. Aug 26, 2013

### Stephen Tashi

I think you'll get more useful responses if you list a few mathematical methods that you know about and ask if they have practical applications. Or ask about practical problems you understand and request mathematics that might apply.

3. Aug 26, 2013

### Keith Young

Thanks Stephen.

Is it better making individual threads, or lump them in here?

The first one I'd like to know is what are some real world uses for Green's Theorem? Particularly in the Engineering field, and if you know of any uses for race cars that would be even more ideal.

4. Aug 27, 2013

### SteamKing

Staff Emeritus
Green's Theorem is the basis for tools like planimeters, which measure the area of irregularly shaped regions. Until the advent of computers, most engineering offices would own a planimeter. For calculating moments of area and such, more expensive instruments called integrators would be used, but they were not as common.

Green's Theorem can still be used to do these same calculations numerically with a computer. If you can describe the boundary of a region using straight lines, arcs, or other curves, you can calculate the area and the various moments of the region without trying to break it up into squares or triangles. GT is quite a practical tool, but it is rarely presented as such in most curriculums.

5. Aug 27, 2013

### rcgldr

differential equations - re-entry and super-sonic ballistics trajectories.

finite field math - error correction code (like Reed Solomon). Used in hard drives.

6. Aug 27, 2013

### Keith Young

Thanks, one of the topics I was planning was the ascent and descent of a sounding rocket.

7. Aug 27, 2013

### Boorglar

Prime Testing and Prime Factorization: fundamental in cryptography (RSA, for example) used in security systems.
For the same applications, a lot of Number Theory actually.

Hyperbolic cosine: it describes the shape of a catenary, a long chain hanging from two poles by its own weight. In bridge designs and architecture.

And there's the Cornu spiral, used to smooth the transition when a train enters a circular curve. Railroad tracks and Highway engineering (close enough to your races, I guess :P)http://en.wikipedia.org/wiki/Euler_spiral

8. Aug 27, 2013

### Keith Young

Thanks Boorglar!