A uniformly charged rod (length = 2.0 m, charge per unit length = 3.0 nc/m) is bent to form a semicircle. What is the magnitude of the electric field at the center of the circle?

84.82N/C.

Explanation:

The x-components of the electric field cancel; therefore, we only care about the y-components.

The y-component of the differential electric field at the center is

.

Now, let us call the charge per unit length, then we know that

;

therefore,

Integrating

Now, we know that

and the radius of the semicircle is

therefore,

i was thinking more like reflects green light, just not sure