(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known dataThe electrical potential can be described by the following equation:

V= 200/(x^{2}+ y^{2})^{1/2}find dV when x=2 and y=1

2. Relevant equations

n/a

3. The attempt at a solution

dv/d(x,y) = ∂/∂x + ∂/∂y

=200/(x^{2}+ y^{2})^{(1/2)}+200/(x^{2}+ y^{2})^{(1/2)}

replace variables with C where necessary and rearrange for easy of deriving =200(x^{2}+ C)^{(1/2)}+200(C + y^{2})^{(1/2)}

Chain rule and exponent rule

=200(-1/2)(2x)(x^{2}+ C)^{(-3/2)}+200(-1/2)(2y)(C + y^{2})^{(-3/2)}

=-200x(x^{2}+ C)^{(-3/2)}+ -200y)(C + y^{2})^{(-3/2)}

=-200x(x^{2}+ y^{2}) )^{(-3/2)}+ -200y)(x^{2}+ y^{2})^{(-3/2)}

Then I plug in the values x=2 and y=1 and dV=-53.7 V/m, I'm not very confident with multivariable calculus and just wanted to check to see if this is right.

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# Homework Help: Electric Potential Derivative

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