# The current and magnetic field of an ideal solenoid.

1. Mar 18, 2009

### winbacker

This is not a homework question, it's just to help my conceptual understanding of two quick things:

Suppose you have an ideal solenoid placed horizontally in front of you. The current is traveling (spiralling) from your left to your right.

What direction is the magnetic field inside the loop going in? In the same direction as the current(to the right), or the opposite direction (or the left)?

In other words, inside an ideal solenoid, are the current and magnetic field in the same direction or opposite direction?

Also
In circuit diagrams, the current always flows from the + terminal to the - terminal right? In some diagrams, the large terminal is replaced by what appears to be a "capital epsilon". The symbol stands for EMF (Electromotive Force). I assume the current begins at the EMF terminal and ends at the other (smaller one?).

If anyone could confirm this info for me it would be a great help.

2. Mar 18, 2009

### Vuldoraq

The current and the magnetic field are always at right angles to each other.

It is true that the magentic field flows in the same direction as the net current flow, but only in this special case.

For emf see here: http://en.wikipedia.org/wiki/Electromotive_force

Also try to post int the general questions forum if it's not a homework related question!