Spin (physics) discrete angular momenta despite having no orbital angular momentum. In some ways, spin is like a vector quantity; it has a definite magnitude, and it has a "direction" (but quantization makes this "direction" different from the direction of an ordinary vector). All elementary particles of a given kind have the same magnitude of spin angular momentum, which is indicated by assigning the particle a spin quantum number. The SI unit of spin is the (N·m·s) or (kg·m·s), just as with classical angular momentum. In practice, spin is given as a dimensionless spin quantum number by dividing the spin angular momentum
Orders of magnitude (numbers) kilo- (k) (; one hundred thousand or a lakh). ISO: mega- (M) ISO: giga- (G) ISO: tera- (T) ISO: peta- (P) ISO: exa- (E) ISO: zetta- (Z) ISO: yotta- (Y) Orders of magnitude (numbers) This list contains selected positive numbers in increasing order, including counts of things, dimensionless quantity and probabilities. Each number is given a name in the short scale, which is used in English-speaking countries, as well as a name in the long scale, which is used in some of the countries that do not have English as their national language. ISO: yocto- (y) ISO: zepto- (z) ISO: