Presume that you are given an expression for the electric potential V(x,y) as a function of x and y valid for points in the first quadrant of a Cartesian coordinate system and asked to find the x-component of the electric field at (4.00cm,5.00cm). How do you discover it?
Ans:
If you alternative the given values of x and y into V(x, y) first, the result is a constant. The derivative of a constant is forever zero. A side note. The specified values are written with three significant figures. Upon converting them to meters they must still have three significant figures. Specified the coordinates (4.00cm, 5.00cm) with three significant figures write them with three significant figures as (0.0400m,0.0500m) not with two significant figures as (0.040m,0.050m) and not with one significant figure as (0.04m,0.05m).