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 ANSWER: 122.36

Respuesta :

Answer:

122.36

Explanation:

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

[tex]d=\sqrt{0.32^2+0.59^2}=0.67m[/tex]

The force between them is given as

[tex]F_1=\frac{1}{4\pi \epsilon_0}\frac{4*18*10^-12}{0.67^2}= 1.44N[/tex]

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

[tex]\theta_1=90^{\circ}+\tan^{-1}\frac{0.32}{0.59}=118.47^{\circ}[/tex]

Now,

The force between 1 and 3 is

[tex]F_2=\frac{1}{4\pi \epsilon_0}\frac{4*2*10^{-12}}{0.79^2}= 0.115N[/tex]

As the force is attractive it is along negative x direction so the angle will be given as = [tex]\theta_2 = 180^{\circ}[/tex]

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

= [tex]1.44\cos(180-118.47)^{\circ}+0.115=0.801[/tex]

And the positive y component = [tex]1.44\sin(180-118.47)^{\circ}=1.26[/tex]

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

[tex]90^{\circ}+\tan^{-1}\frac{0.801}{1.26}=122.36^{\circ}[/tex]