What Is the Interpretation of an Integral Equation with a Proportional Variable?

AI Thread Summary
The discussion centers on interpreting the integral equation ΔV = -∫_a^b E · ds, which represents the change in electric potential between two points. It is explained that the integral can be viewed as the limit of a summation process, where ΔV is the cumulative effect of the electric field along a path. The relationship is compared to work done by a force, emphasizing that small changes in potential can be summed to yield the total change. The interpretation highlights that the integral captures the total potential difference as one moves from point a to point b in the presence of an electric field. Understanding this relationship is crucial for grasping the concept of electric potential in physics.
Anti Hydrogen
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Homework Statement
Hi, I'm trying to understand the case when a variable is proportional to that which is under a integral sign, for example
$$\Delta V = - \int_a^b \vec E \cdot d \vec s$$

What could be a interpretation of this equation?
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Anti Hydrogen said:
Homework Statement:: Hi, I'm trying to understand the case when a variable is proportional to that which is under a integral sign, for example
$$\Delta V = - \int_a^b \vec E \cdot d \vec s$$

What could be a interpretation of this equation?
Relevant Equations:: Thanks

Thanks
An integral is the limit of a summation process. Here we have ##\Delta V## as (the sum of) the product of the electric field multiplied by a length. You could compare this with:
$$W = \int_a^b \vec F \cdot d \vec r$$
 
Essentially this is a restatement what @PeroK was saying: consider the change in the potential ##\delta V## along a small displacement vector ##\delta \vec{r}## in a region where the electric field is ##\vec{E}##, $$\delta V = -\vec{E} \cdot \delta \vec{r}$$Now if we sum up all of these small changes along some path $$\sum \delta V = -\sum \vec{E} \cdot \delta \vec{r}$$If you now take the limit as the length of the displacement vector approaches zero, that is ##\delta \vec{r} \rightarrow d\vec{r}## and consequently also ##\delta V \rightarrow dV##, the sums turn into integrals $$\int_{V_{1}}^{V_{2}} dV = -\int_{a}^{b} \vec{E} \cdot d\vec{r}$$Apologies if I abused any notation! For this specific integral, the interpretation is the change in potential going from ##a## to ##b##.
 
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Anti Hydrogen said:
Homework Statement:: Hi, I'm trying to understand the case when a variable is proportional to that which is under a integral sign, for example
$$\Delta V = - \int_a^b \vec E \cdot d \vec s$$

What could be a interpretation of this equation?
Relevant Equations:: Thanks

Thanks
What variable is proportional to what under the integral sign? Are you saying that ##\Delta V## is proportional to ##\vec E \cdot d \vec s?## @PeroK said it right, look at the line integral as a summation.
 
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