# Where did the formula $Φ(x,y,z) = x^3y - z^2$ come from? How does it define a scalar field? [closed]

I want to ask that why $Φ(x,y,z) = x^3y - z^2$. I don't understand this relation? Can someone make sense of this equation.

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In what context? It looks like a potential function, and it's a scalar because all the things on the right are scalars. But without any context at all, there is no possibility to help. – tpg2114 Jan 29 at 2:41
(I am guessing this is from a homework question in electrodynamics?) This is simply a definition of some function $\Phi$. Think of it as giving a name to the expression on the RHS, simply for convenience. – David M. R. Jan 29 at 3:28

## closed as not a real question by Manishearth♦Jan 29 at 4:16

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.

If the x,y and z coordinates of a particular point in space is (1,2,3), then the number corresponding to that point in space, for the scalar field in your equation, is $x^3y - z^2 = 1^3*2 - 3^3 = -7$. That is, you simply substitute the coordinates of a particular point in space into the equation, and you arrive at the number corresponding to that point.