Charged conducting cylinders in contact

The electrostatics of two parallel charged conducting cylinders in contact is discussed, for arbitrary radii of the cylinders. The charges per unit length on the cylinders are in proportion to their radii, as found by Adams in 1935. The charge distributions on the cylinders are calculated. The force acting between the cylinders is found to be different from that obtained by Adams. When one cylinder is much larger than the other, the force between them is proportional to the radius of the smaller. •Exact force between charged conducting cylinders in contact.•Conducting cylinders in contact have charge in proportion to radius.•Conducting cylinders in contact have equal average charge densities.