What diameter glass beads weighing approximately 5g each?

The density of ordinary glass beads is about 2.5g/cm³. We can calculate the diameter by combining the sphere volume formula \(V=\frac{4}{3}\pi r^3\) (where r is the radius) and the mass formula \(m = \rho V\) (where \(\rho\) is the density and m is the mass). First, calculate the volume of the glass bead. Substitute \(m = 5g\) and \(\rho=2.5g/cm³\) into the mass formula, and we can get \(V=m\div\rho = 5\div2.5=2cm³\). Then substitute the volume into the sphere volume formula to reverse the radius: \(2=\frac{4}{3}\times3.14\times r^3\). After calculation, \(r^3\approx0.477cm³\) and \(r\approx0.782cm\). Finally, it can be inferred that the diameter is about 1.56cm, which is 15.6mm.

There are slight tolerances in the diameter and density during the production of glass beads, which will lead to small deviations in weight. According to the conventional product specifications of glass beads, a glass bead with a diameter of 16mm is very close to 5 grams in weight. This specification of glass beads is not only common in daily decorative and craft scenarios but also can be seen in some small entertainment equipment. It is a mainstream specification that meets the requirement of a single weight of about 5 grams.