I. Microscopic polarization An atom can be modeled as a light, spherical cloud o
ID: 1771094 • Letter: I
Question
I. Microscopic polarization An atom can be modeled as a light, spherical cloud of electrons of uniform volume density centered on a small, massive nucleus. A. At t, the atom is placed in an electric field external to the atom. Electron cloud 1. In what direction is the net force on the electrons? t0 What happens to the charge distribution of the atom after 1,2 Explain 2. B. Assuming the electron cloud remains spherical, how will the atom be arranged in equilibrium? What force on the electrons balances the force by the net electric field external to the atom?Explanation / Answer
A
1.) Net force on electrons is in the direction opposite to the electric field.
2.) Due to net force on electrons, electron cloud will shift downwards (opposite to electric field). Hence, positively charged nucleus is not at the center of the electron cloud after time t0.
B.
In equilibrium, the positive center and the center of negatively charged electron cloud will be apart. The separation will be such that the internal electric field (created due to charge separation) will balance out the external field.