Reference no: EM13966496

Consider a ring of radius 3.5 cm with a uniform linear charge density λ = 4.6 C/m. Calculate the E field at a distance 3 cm from the center along the axis of the ring. 

2.79×10¹² V/m A part of the above ring is cut off so that the remainder subtends an angle 66° at the center of the circle. Find the magnitude of the E field at the center of this new arc, assuming that the three-fourths of the charge was lost in the cutting process.

can someone answer the second question and  a similar one  in the following?

Two circular disks, each of area 1.70×10^-4 m², are situated parallel to one another (see figure). The distance between them is small compared with their radii. Both disks are uniformly charged; their charges per unit area are σ = 2.40×10^-5 C/m² for one and -σ = -2.40×10^-5 C/m² for the other. Compute the force exerted by one on the other. You may assume for the purposes of calculating the electric field that the discs are infinite in extent