Electric Field Due To A Uniformly Charged Ring MCQ - Practice Questions with Answers

In this concept we are going to derive the electric field due to continous charge on a ring -

In this one should notice that there symmetry in this situation. Every element dq can be paired with a similar element on the opposite side of the ring. Every component  perpendicular to the x-axis is thus cancelled by a component  in the opposite direction.
In the summation process, all the perpendicular components  add to zero. Thus we only add the  components, which all lie along the +X direction, and this is a simple scalar integral. From Coulomb’s Law in vector form,

As we integrate around the ring, all the terms remain constant

 Also,          

So, the Net electric field is - 

Graph  between E and X - 

                                                                                           If,   

                                                                                           ,