1.What are the principal differences between welding, brazing, and soldering? You may need to consult another reference
2.Electromagnetic radiation may be treated from the classical or the quantum mechanical perspectives. Briefly compare these two viewpoints.
3.Compare those factors that determine the characteristic colors of metals and transparent nonmetals.
4.Are the elemental semiconductors silicon and germanium transparent to visible light? Why or why not?
5.Which of the following oxide materials when added to fused silica (SiO2) will increase its index of refraction: Al2O3, TiO2, NiO, MgO? Why?