I have no idea what these answers are, any help would be highly appreciated please! 1.) Why is hematite the most important ore of iron, although magnetite contains a higher percentage of iron? 2.) give two examples of minerals which are precipitated by the evaporation of seawater. 3.) what are some advantages and disadvantages of a synthetic gemstone to the buyer? Thank you sooo much! :D
This Site Might Help You. RE: What is a commutator? What is a commutator? My friends have said something about it but I'm not really understanding it.
A commutator is an electrical switch that periodically reverses the current in an electric motor or electrical generator. Commutators enable motors to run on, and generators to produce, direct current instead of alternating current. More generally, commutators can be used to convert between direct and alternating current.
Another place where you see the term 'commutator' is in quantum mechanics or in linear algebra. If A and B are operators, it is possible that AB and BA are different. The difference, AB-BA is called the commutator of A and B, and is written [A,B].
