Find the electric field at the centre of a uniformly charged semicircular ring of radius R. Linear charge density is `lamda`

Options

A. `(lamda)/(2piepsi_(0)a)`
B. `(lamda)/(4epsi_(0)a)`
C. `(lamda)/(2piepsi_(0)a^(2))`
D. `(lamda^(2))/(4piepsi_(0)a)`

Answer

B

Explanation

`E=sum(dQ)/(4piepsi_(0)a^(2))=sum(lamdadl)/(4piepsi_(0)a^(2))`
`therefore E=(lamdapia)/(4piepsi_(0)a^(2))=(lamda)/(4epsi_(0)a)`