Reverse engineering potential and kinetic energy

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SUMMARY

The discussion centers on the relationship between potential energy (PE) and kinetic energy (KE), specifically the equations PE=M*V and KE=(1/2)*(M*V^2). Participants clarify that PE is not the same as momentum and that PE is the derivative of KE. The conversation also explores the concept of antiderivatives, questioning the existence of higher-order expressions of energy beyond the second antiderivative. Ultimately, it concludes that while higher-order differential equations can be constructed, they do not typically represent observed natural laws.

PREREQUISITES
  • Understanding of basic physics concepts: potential energy and kinetic energy
  • Familiarity with calculus: derivatives and antiderivatives
  • Knowledge of momentum and its distinction from energy
  • Basic grasp of differential equations and their applications in physics
NEXT STEPS
  • Research the implications of higher-order differential equations in physics
  • Study the relationship between energy, mass, and velocity in classical mechanics
  • Explore the concept of generalized momentum and its derivation from the Lagrangian
  • Investigate the physical phenomena represented by various antiderivatives of mass with respect to velocity
USEFUL FOR

Students of physics, educators, and researchers interested in the mathematical relationships between energy forms and their implications in physical laws.

q-ball
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The equation for momentum (potential energy) is PE=M*V.

The equation for kinetic energy is KE=(1/2)*(M*V^2).

You will notice that PE is the derivative of KE. and then you might add that M, simply Mass, is the derivative of PE.

However, because M is simply a scalar quantity, and the other functions are expressions of energy added TO mass, I might suspect the correct approach is to say that you start with mass and take the *antiderivative* with regard to velocity.

and there is more, but first some observations.

PE and KE are two separate expressions of energy. upon inspection we find that they have completely different effects, when an object, let's say a solid ball, encounters a medium:

1A) PE: the solid ball encounters another solid ball. there is an elastic conservation of momentum as the second ball goes off on a particular trajectory, the angle and velocity of which are accounted for by Potential Energy.

1B) PE: the solid ball encounters a wall of oatmeal. exactly how far the ball continues before coming to rest is a function of its momentum (PE), notwithstanding fluid dynamics.

2) KE: the solid ball encounters a thin, hard barrier such as a sheet of glass. if the KE is sufficient, the solid ball will overcome the barrier.

As we can see those are two completely different phenomena. Of course, otherwise they would have the same name, being the same thing. But they don't and they aren't. They are separate phenomena.

Now for the questions.

We can easily deduce a third antiderivative. ??=(1/6)*(M*V^3) so, what sort of energy does that represent? what
physical phenomenon does it describe? as in 1A), 1B), and 2), and ...?

that is what I am most interested in.

but we can also ask, what prevents nature from making use of an infinite array of further antiderivatives in an infinite series of discrete expressions of energy? who says we must stop at the second antiderivative (KE)? Shouldn't there be a name for this set of equations, this class of expression, which goes from the 0th to the nth antiderivative of Mass with regard to Velocity?
 
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q-ball said:
The equation for momentum (potential energy) is PE=M*V.
Momentum is not potential energy. Momentum is not energy. So the rest of your post doesn't really make sense.

I've downgraded the thread level from A to I.
 
q-ball said:
The equation for momentum (potential energy) is PE=M*V.
No, momentum is not PE.

q-ball said:
notice that PE is the derivative of KE
No, the closest that you could come to this is that the generalized momentum is the derivative of the Lagrangian with respect to the generalized velocities.

q-ball said:
who says we must stop at the second antiderivative (KE)?
The laws of nature that we have observed thus far are second order differential equations with respect to the coordinates. There is nothing mathematically preventing you from constructing higher order differential equations, but they don't seem to represent natural laws so most people don't bother.
 
Dale said:
The laws of nature that we have observed thus far are second order differential equations with respect to the coordinates. There is nothing mathematically preventing you from constructing higher order differential equations, but they don't seem to represent natural laws so most people don't bother.
I suppose that answers the question then.
 

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