Physics Phun

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ok guys, here's a little brain teaser for you:

One mass (m1) is moving with constant velocity towards another mass (m2) which is at rest. M2 has a spring with spring constant k on the near side. When the two masses collide what is the maximum compression distance of the spring? (the collision is 1-D and the surface they are on is frictionless).

Im thinking that the max compression for the spring will be found using the potential energy equation for springs.

something like:
sqrt[((m1)(Vo)^2)/k]=x(max compression distance of the spring)

The only thing that bugs me is that mechanical energy and momentum are completely conserved... which is why Im skeptical that the spring compresses at all...

WILL YOU TEACH ME PHYSICS PLZ!?!?!

You don't have to yell. What about physics do you want to learn? The topic of "physics" is so broad that one doesn't necessarily know where to start explaining.

i'd like to learn about inertia

Basic Mechanics and Newton's three laws are a good place to start:

I. If the net outside forces acting on a system are equal to zero, then the body is in equilibrium, or it continues to do whatever it is doing... (be that translating(moving in a straight line), rotating(spinning about an axis), or at rest (in YOUR reference frame)).

II. This is the law regarding force. Force is the change in inertia of a body. If a net external force acts upon a system/body the system/body accelerates in the direction of the NET force. With vectors this net force magnitude is equal to the body/system's acceleration times its mass. Also, I mention vectors because they are going to be how you define what the net direction/magnitude of the accleration is.

III. This law is the most commonly known law. It is the law of action and reaction, or causality. For any given force exerted on an object by another object, there is an equal and opposite force (reaction) exerted upon the original object. This however, may lead to different results for each object, depending on several factors, some of which include other forces acting upon the objects which are independent of the said action/reaction, and mass (this is important in conservation of momentum).

If you want to learn more, I suggest getting a book of some sort. Assuming that you are AS, hackermage, I would suggest a high school physics book (if you are JH or older), and if you are older than HS, get Feynman's Lectures On Physics. They are simply amazing and relate physics to everything, as it should be taught.

If you want to discuss anything in mechanics in more detail, just ask, I dont promise an answer but I'd love to start some threads on tihs stuff.

Energy and momentum are conserved. Doing the calculation in the center of mass frame means that the total momentum is always zero and the maximum spring compression occurs when the two masses are at rest so that the kinetic energy is zero and the potential energy is maximized.

m1 * v1 = -m2 * v2

1/2 k * x^2 = 1/2 (m1 * v1^2 + m2 * v2^2)

I love physics, and understand almost every aspect I've researched on it, I've read many books, and the theory is easy for me to grasp.

However the actual equations confuse me, I'm learning, but I'm finding it the hardest aspect..

I've decided to go back and revise my basic algebra skills, progressing from there.

You think this is the best way to go?

yeah. The only way you are gonna get good at finding physical relationships is by having a strong base in equation manipulation and geometry/trig.

After you know how things work mathematically, you can take several simple relationships found in physics and apply them to a broad spectrum of problems. And thats where the true beauty of physics will shine.