Some sample questions from this category:
* What is a subatomic particle?
* For every particle of matter there is a corresponding particle with identical mass and spin but opposite charge. What are these corresponding particles called?
* Everything must be weighed, even subatomic particles. What standard term is used for expressing the mass of protons, neutrons and electrons?
* To gain some perspective on the relative sizes of subatomic particles, if an atom was the size of a baseball field, what could represent the nucleus?
* The great physicist Max Planck hypothesized that some types of energy could not take on any value. The value must be a multiple of a very small quantity. What is that quantity called?