A thread having linear charge density `lamda` is in the shape of a circular arc of radius R subtending an angle `theta` at the centre.
(a). Find the electric field at the centre.
(b). Using the epression obtained in part (a) find the field at the centre if the thread were emicircular
(c). Find the field at centre using the expression obtained in part (a) for the case `thetato`0. Is the result justified?
(d). A thread having total charge Q (uniformly distributed is in the shape of a circular arc of radius R subtending an angle `theta` at centre. write the expression for the field at the center. Obtain the field when` thetato0`. Make sure you understand the difference in case. (c) and (d).

Answer

(a). `E=(2Klamda)/(R)sin((theta)/(2))`
(b). `E=(2Klamda)/(R)`
(c) `E=0`
(d). `E=(KQ)/(R^(2))`