Identify the sealed glass vacuum tube containing an electron beam that is focused on a phosphor-coated glass screen when light is emitted.

Which physical unit is defined as the field intensity that produces one newton (N) of force per ampere (A) per meter of conductor?

Which of the following materials or elements is highly effective for making a permanent magnet?

In the early nineteenth century, who demonstrated that there are fourteen space lattices, or regularly repeating arrangements of points in space, that differ in symmetry and geometry?