A period on the periodic table is a horizontal row. The atoms in this row show a trend in their width, and in the amount of work needed to make them an ion, among the fe â¦ w other similarities.
A coordinate grid has two perpendicular lines, or axes, labeled like number lines. The horizontal axis is called the x-axis. The vertical axis is called the y-axis. The point where the x-axis and y-axis intersect is called the origin. The numbers on a coordinate grid are used to locate points. Each point can be identified by an ordered pair of numbers; that is, a number on the x-axis called an x-coordinate, and a number on the y-axis called a y-coordinate. Ordered pairs are written in parentheses (x-coordinate, y-coordinate).
The mid-plane of the laminate lies in the XY-plane so that half its thickness is above the plane and half is below. Hence, the XY-plane is a plane of symmetry and II xz yz 0 o Bodies of revolution have two planes of symmetry. For the configuration shown, the XZ and YZ planes are planes of symmetry. Hence, all products of inertia are zero about the X, Y, and Z axes. o Products of inertia are found either by measurement or calculation. Calculations are based on direct integration or on the â body build-up â technique.