1. In ionic materials, how does the size of the component ions affect the extent of elec- tronic polarization?
2. Can a material have an index of refraction less than unity? Why or why not?
3. Compute the velocity of light in diamond, which has a dielectric constant Er of 5.5 (at frequencies within the visible range) and a magnetic susceptibility of -2.17 X 10-5.
4. The indices of refraction of fused silica and a polystyrene within the visible spectrum are 1.458 and 1.60, respectively. For each of these materials determine the fraction of the relative dielectric constant at 60 Hz that is due to electronic polarization, using the data of Table 18.5. Neglect any orientation polarization effects.
5. Using the data in Table 21.1, estimate the dielectric constants for silica glass (fused silica), soda-lime glass, polytetra- fluoroethylene, polyethylene, and poly- styrene, and compare these values with those cited in Table 18.5. Briefly explain any discrepancies.
6. Briefly describe the phenomenon of disper- sion in a transparent medium.