Charge 1 of +4 micro-coulombs is placed at the origin, charge 2 of +18 micro-coulombs is placed at x = +0.32 m, y = -0.59 m, charge 3 of -2 micro-coulombs is placed at x = -0.79 m, y = 0 m. measured counter-clockwise in degrees, what is the angle of the total electric force vector on charge 1?
correct 122.36

122.36

Explanation:

The distance (d) between Charge 1 and 2 can be calculated as:

The force between them is given as

The angle of this force with positive x-axis is given as

Now,

The force between 1 and 3 is

As the force is attractive it is along negative x direction so the angle will be given as =

So the negative x component of the resultant force will be calculated as

=

And the positive y component =

So the angle of the resultant with positive x axis will be