- #1
Jrlinton
- 134
- 1
Homework Statement
The electric potential at points in an xy plane is given by V = (1.5 V/m2)x2 -(2.9 V/m2)y2. What are (a) the magnitude of the electric field at the point (3.9 m, 2.9 m) and (b) the angle that the field there makes with the positive x direction.
Homework Equations
The Attempt at a Solution
Okay, Part a I have completed correctly by multiplying the derivative of the difference potential and the negative of direction component for both x and y.
So for x we get
1.5*-2=-3(x)
And y
2.9*-2=-5.8(y)
Inserting the given values for x and y I get that
x=-11.7
y=-16.82
Using pythagorean theorem I get that
r=20.4891 V/m
The problem I have (and feel silly about) is coming up with the angle in part b
I think it should simply be:
arctan(-16.82/-11.7)+180°
=235.178° or -124.823° ⇐This was incorrect