# Conceptual - Loop of Current

1. Feb 23, 2012

### GeorgeCostanz

1. The problem statement, all variables and given/known data

Answer the following with regard to the current loop shown in the figure.

http://i.imgur.com/Lkp4D.gif

TRUE OR FALSE:

The B Field at C points into the plane of the paper.

If an external magnetic field directed out of the plane of the paper were introduced, the torque on the coil would be zero.

The magnetic moment of the loop points into the plane of the paper.

The B field inside the loop points out of the plane of the paper.

The coil behaves like a bar-magnet with its axis along the plane of the paper.

The B Field at B is greater than at A.

2. Relevant equations

3. The attempt at a solution

The B Field at C points into the plane of the paper. (T)

If an external magnetic field directed out of the plane of the paper were introduced, the torque on the coil would be zero. (F)

The magnetic moment of the loop points into the plane of the paper. (F)

The B field inside the loop points out of the plane of the paper. (F)

The coil behaves like a bar-magnet with its axis along the plane of the paper. (T)

The B Field at B is greater than at A. (T)

i hate the right hand rule

Last edited: Feb 23, 2012
2. Feb 23, 2012

### PeterO

Your suggestions T, F, F, F, T, T

I don't agree with many, but cannot see the diagram and answers at the same time.

I agree with the first, but very few of the rest - i think

Last edited: Feb 23, 2012
3. Feb 23, 2012

### GeorgeCostanz

sorry, it's a true or false question
6 statements

4. Feb 23, 2012

### PeterO

Was the loop of wire actually that crazy shape, or did you just have trouble drawing a circle?

5. Feb 23, 2012

### GeorgeCostanz

haha na thats the shape

6. Feb 23, 2012

### PeterO

My interpretations

7. Feb 25, 2012

### GeorgeCostanz

well the answers ended up being:

True: The B Field at C points into the plane of the paper.

True: If an external magnetic field directed out of the plane of the paper were introduced, the torque on the coil would be zero.

False: The magnetic moment of the loop points into the plane of the paper.

True: The B field inside the loop points out of the plane of the paper.

False: The coil behaves like a bar-magnet with its axis along the plane of the paper.

True: The B Field at B is greater than at A.

i got messed up on the bar-magnet question, could have sworn my professor told us it was true

and i'm guessing the b-field inside the loop would be using the right hand rule, placing your thumb on the underside of the current (thinking 3-D) and your fingers as the b-field point outwards

no idea why my brain is struggling to compute these simple right hand rules