# energy field, sum of charges [closed]

Let's say I have a linear field with one "point source" of "power" $B$. At a certain distance, I have $A = \frac{B}{d^2}$.

Now I have a grid of size $X \times Y$, with $N$ sources at random locations.

How can I calculate the addictive effect of all $N$ of the sources' powers ?

$A$ and $B$ can be anything suitable. Example $N$ light sources (like incandescent light bulbs).

$S_1 : 20$ Watts

$S_2 : 40$ Watts

$S_3 : 60$ Watts

$S_4 : 120$ Watts.

They are at the 4 corners of a square, side is 2 meters.

What is the intensity of the light at the center of the square?

-
 Welcome to Phsics.SE! "What is the fastest algorithm to calculate the total A for each point on a discrete grid..." is not a physics problem, but one of optimizing a calculation. "How can I calculate the addictive effect of all N of the sources' powers?" is a physics problem, but it is one that has to be added to the definition of the field (and Dan has given you the usual answer: it's linear), rather than something that can be deduced from the rest of what you gave us. – dmckee♦ Oct 7 '11 at 16:09 dmckee, I appreciate the feedback and modify my question to outline "linear field". I don't understand why did you close the question. If it is ambiguous or vague or etc... please let me know and I will correct it. thanks. – Massimo Oct 7 '11 at 20:44

## closed as not a real question by dmckee♦Oct 7 '11 at 16:32

It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, see the FAQ.

Your $A$ field is likely linear.
This means that if you have two sources $S_1$ and $S_2$, the $A$ field at point $p$ will be $$A_p= \frac{B_1}{d_{1p}^2} +\frac{B_2}{d_{2p}^2}$$
Where $d_{1p}$ and $d_{2p}$ are the distances from $S_1$ and $S_2$ to $p$, respectively. This formula generalizes to any number of sources, as well.