A thin glass rod is bent into a semicircle of radius r. A charge +Q is uniformly distributed along the lower half, as shown in fig. The electric field E at P, the center of the semicircle, is

A thin glass rod is bent into a semicircle of radius r. A charge +Q is uniformly distributed along the upper half, and a charge -Q is uniformly distributed along the lower half, as shown in fig. The electric field E at P, the center of the semicircle, is

Charges q is uniformly distributed over a thin half ring of radius R . The electric field at the centre of the ring is

Charges q is uniformly distributed over a thin half ring of radius R . The electric field at the centre of the ring is

Charge q is uniformly distributed over a thin half ring of radius R . The electric field at the centre of the ring is

A wire of length l and charge q is bent in form of a semicircle. The charge is uniformly distributed over the length. The electric field at the centre of semicircle is

A wire of length l and charge q is bent in form of a semicircle. The charge is uniformly distributed over the length. The electric field at the centre of semicircle is

semicircle of radius R. The electric field at the centre is -

Figure shows a rod AB, which is bent in a 120^(@) circular arc of radius R. A charge (-Q) is uniformly distributed over rod AB. What is the electric field vecE at the centre of curvature O ?