A semi-circular arc of radius ‘a’ is charged uniformly and the charge per unit length is A. The electric field at the centre of this arc is
Options:
(a) `lambda/(2piepsilon_0a)`
(b) `lambda/(2piepsilon_0a^2)`
(c) `lambda/(2pi^2epsilon_0a)`
(d) `lambda^2/(2piepsilon_0a)`