Formulating Physical Quantities, Energy & Conservation of Energy

AI Thread Summary
The discussion focuses on formulating relationships between physical quantities and energy conservation in physics. The original poster seeks confirmation on a mathematical expression that links various physical quantities (Pq1, Pq2, etc.) to energy, proposing that energy remains constant despite variations in these quantities. Responses indicate that the proposed formulation lacks physical meaning and units, emphasizing that mere symbols do not convey valid physical concepts. A suggestion is made to consider the model as a variant of Lagrangian mechanics, using a pendulum as an example to illustrate energy conservation principles. The conversation highlights the importance of grounding mathematical expressions in physical reality and established principles.
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1. Homework Statement


Hi, I've been thinking about a formulation regarding "physical quantities" (that is, the quantities that specifically constitute the object of measurement for Physics), energy, and the conservation of energy. It would be very helpful for me that you could confirm me the thing is mathematically right, so here it goes (I just want to know if what I'm going to formulate is a compatible and correct, no matter if ugly or beautiful, mathematical expression about physical quantities, energy, and conservation of energy):

Let " Pq1 " be the "Physical quantity 1" (a certain physical quantity of a certain kind). So we'll have the physical quantities Pq1 , Pq2 , Pq3, ... , Pqn.

Now I am wondering: "in which ways could these physical quantities vary?", that is, "what combinations or configurations of values would be acceptable for Pq1 , Pq2 , Pq3, ... , Pqn "?

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2. Homework Equations


To anwer to this: 1º Step) I introduce "Energy", in a way :


Energy ( Pq1 , Pq2 , Pq3, ... , Pqn ) = Energy​


(Notice that, in this case, "Energy" is being the only physical quantity that is not following the notation Pqi ; but this is unimportant).

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3. The Attempt at a Solution


... and, finally, 2º Step): I establish the set of equations: The space Pqi can support any configuration so that...


Energy ( Pq1 , Pq2 , Pq3, ... , Pqn ) = Energy

Energy = Constant​


(Or, in short, Pqi can assume any combination of values so that Energy ( Pq1 , Pq2 , Pq3, ... , Pqn ) = Constant )

Is this concept right? and if it is not, what would be the correction?

Thank you very much :smile: !
 
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You should read a good introductory physics book. There is no physical content in your expressions. You cannot just write symbols down and have it make sense. Physical quantities have units and meaning.
 


(Op here. Additional note to my opening post in case it could help someone:

Later I realized the suggested model is simply an easy variant of a Lagrangian.

Perfect illustrating example: a pendulus. Energy (position, velocity) = -Energy (position) + Energy (velocity) = constant.

Other thing: the constant character of Energy value has to do with up to 2 important things: 1º) conservation of energy; and 2º) minimization of energy (or principle of least action).

Bests.)
 
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