Why is a conserved vector field a gradient of a certain func

In summary, the reason for the existence of a function whose gradient is equal to a conserved vector field comes from the Fundamental Theorem of Calculus and the concept of conservative force. The work done by a conservative force on a closed curve is zero, while this is not true for non-conservative forces.
  • #1
Za Kh
24
0
I know that if a vector field is conserved then there exits a function such that the gradient of this function is equal to the vector field but am just curious to know the reason of it.
 
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  • #2
Hi ZA,

You of course googled conservative vector field but there must be something that isn't clear to you. What specifically ?
 
  • #3
BvU said:
Hi ZA,

You of course googled conservative vector field but there must be something that isn't clear to you. What specifically ?
Hi! I've figured this out, by the stocks theorem and that the work done by a conservative force on a closed curve is zero but why it isn't true for the non conservative force?
 
  • #4
That comes from the "Fundamental Theorem of Calculus", that if F is a differentiable function such that F'= f then [itex]\int_a^b= f(b)- f(a)[/itex]. A "conservative force" is the derivative of some "energy function". The integral depends only on the end points, not the path between the end points. The integral around a closed path, since the "end points" are the same point, is 0.
 

1. Why is a conserved vector field a gradient of a certain function?

A conserved vector field is a type of vector field in which the divergence is equal to zero. This means that the vector field is "conserved" or does not change over time. A gradient, on the other hand, is a mathematical operation that takes a scalar function and produces a vector field. When a vector field is conserved, it can be shown mathematically that it must be the gradient of a certain function, known as the potential function.

2. What is the significance of a conserved vector field being a gradient?

The fact that a conserved vector field is a gradient has important implications in physics and engineering. It allows us to describe the behavior of a system using a single scalar function instead of a complex vector field. This makes calculations and analysis much simpler and more efficient.

3. How is a conserved vector field related to conservative forces?

In physics, forces that are conservative are those that do not dissipate energy. This means that the work done by the force is independent of the path taken. A conserved vector field is closely related to conservative forces because it describes a force field in which the work done is path independent. This is why conservative forces are often referred to as "conserved" forces.

4. Can a vector field be conserved without being a gradient?

No, a vector field cannot be conserved without being a gradient. This is because the mathematical definition of a conserved vector field requires the divergence to be equal to zero, and it can be shown that this is only possible if the vector field is a gradient.

5. How is a conserved vector field used in practical applications?

Conserved vector fields have many practical applications in physics and engineering. They are used to model and analyze various physical systems, such as fluid flow, electromagnetic fields, and gravitational fields. They also play a crucial role in the study of conservative forces and the conservation of energy in physical systems.

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