# Toroid physics homework

1. Feb 17, 2008

### JasonBourneV

Inside the toroid, in which direction does the magnetic field point, if the current is going clockwise around the loop?

So I tried to consider the fields due to two points on opposite sides of the toroid. Then I got stuck becuase I don't know what direction their fields added up. What do I do?

2. Feb 17, 2008

### Staff: Mentor

Use a right hand rule to determine the direction of the field.

3. Feb 17, 2008

### JasonBourneV

I did, I got counterclockwise but that wasn't the answer.

4. Feb 17, 2008

### Staff: Mentor

Counterclockwise isn't correct.

Imagine the loop on the surface of a table (the x-y plane). If the current is going clockwise, use the right hand rule in either of two ways:
(1) use it to find the field around any segment of current (that will tell you the field direction in the center of the loop)
(2) apply it direction to the current loop

The answer must be out of the table or into the table.

Method one is described here: http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/magcur.html#c1"

Last edited by a moderator: Apr 23, 2017
5. Feb 17, 2008

### JasonBourneV

oh... I think I into the table. The current is clockwise, so my fingers curl into the table. Is that right?

Last edited: Feb 17, 2008