A small element `l` cut from a circular ring of radius a and `lamda` charge per unit length. The net electric field at the centre of ring is

Options

A. zero
B. `(lamdal)/(4pi epsilon_(0)a^(2))`
C. `oo`
D. `(lamda)/(4pi epsilonl)`

Explanation

(b) `E_("net")=` electric field due to ring at centre without cutting portion electric field due to cutting element is

`E_("net")=0-(q_(0))/(4piepsilon_(0)a^(2))=-(lamdal)/(4piepsilon_(0)a^(2))`
`|E_("net")|=(lamdal)/(4piepsilon_(0)a^(2))`