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
Silver as an investment silver can be instantly bought or sold just like any foreign currency. Unlike holding physical silver, the customer has a claim against the bank for a certain quantity of metal. Digital gold currency providers and internet bullion exchanges, such as BullionVault or GoldMoney, offer silver as an alternative to gold. Some of these companies allow investors to redeem their investment through delivery of physical silver. Derivatives, such as silver futures and options, currently trade on various exchanges around the world. In the U.S., silver futures are primarily traded on COMEX (Commodity Exchange), which is a subsidiary of the New York