A ring of radius R carries a uniform, positive, linear charge density ?. Figure shows a point P in the plane of the ring but not at the center. Consider the two elements of the ring of lengths s1 and s2 shown in the figure at Figure Problem 78 distances r1 and r2, from point P.

(a) What is the ratio of the charges of these elements? Which produces the greater field at point P?

(b) What is the direction of the field at point P due to each element? What is the direction of the total electric field at point P?

(c) Suppose that the electric field due to a point charge varied as 1/r rather than 1/r2. What would the electric field be at point P due to the elements shown?

(d) How would your answers to parts (a), (b), and (c) differ if point P were inside a spherical shell of uniform charge and the elements were of areas s1 and s2?

Transcribed Image Text:

P. 12 S2