Consider a very rough model of a beryllium atom. The nucleus consists of four protons and four neutrons, confined to a small volume of radius 10⁻¹⁵ m . The two 1s electrons form a spherical charge cloud at an average distance of 1.3 10⁻¹¹ m from the nucleus, while the two 2s electrons form another spherical cloud at an average distance of 5.2 10⁻¹¹ m from the nucleus. Determine the electric field at a point just insi

Step-by-step solution

To find the electric field at a point just inside the 2s cloud, we construct a spherical Gaussian surface of radius r = 5.2 10⁻¹¹ m centered at the nucleus. The charge enclosed by this Gaussian surface includes the nucleus and the two 1s electrons. The 2s electrons lie outside this surface and do not contribute to the enclosed charge. Charge of the nucleus, q_n = +4e Charge of the two 1s electrons, q_ 1s = -2e Net enclosed charge, q_ enc = +4e - 2e = +2e Using Gauss's law, the electric field E at this distance is g