-  . . .  as1
- I am using 
 the conventional notation for 
 as the  UNIT VECTORS in the x, y, z directions, respectively. as the  UNIT VECTORS in the x, y, z directions, respectively..
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
 
-  . . .  charge]:2
- I 
 know, I know, I am using the  symbol for two different 
 things.  Well, I said it was the preferred symbol 
 for a scalar field, so you shouldn't be surprised to see it 
 ``recycled'' many times.  This won't be the last! symbol for two different 
 things.  Well, I said it was the preferred symbol 
 for a scalar field, so you shouldn't be surprised to see it 
 ``recycled'' many times.  This won't be the last!.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
 
-  . . .  on.3
- These 
 are rotten examples, of course - the first practical 
 criterion for the variables of which any  is a function 
 is that they should be linearly independent 
 [i.e. orthogonal ] so that the dependence on one 
 is not all mixed up with the dependence on another! is a function 
 is that they should be linearly independent 
 [i.e. orthogonal ] so that the dependence on one 
 is not all mixed up with the dependence on another!.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.