# Homework Help: Torque on a coil of wire in a magnetic field.

1. Feb 9, 2013

### SherlockOhms

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

A rectangular coil has 120 turns of wire and is of dimensions 10 cm by 15 cm. The coil is placed in a uniform magnetic ﬁeld B= 2.6 T such that the ﬁeld lines make an angle of 33 degrees with the direction normal to the coil.
Calculate the magnitude of the torque on the coil if a current of 1.z A ﬂows through it.

2. Relevant equations
Torque = (B)(I)(L)(W)sin(theta)

3. The attempt at a solution
I'm not really sure what to do with the dimensions and turns. L is the length of the loop and W is the width. How do I use the information of the 120 turns to find L and W to fit the above equation?

2. Feb 9, 2013

### TSny

L and W are the dimensions of the loop given in the statement of the problem. Your formula is for one turn of wire (i.e., one loop). You have 120 turns. So, how does that affect the total torque?

3. Feb 9, 2013

### SherlockOhms

So, 120 times the torque for one loop?

4. Feb 9, 2013

### TSny

Sounds very reasonable to me, since each loop experiences the same amount of torque.

5. Feb 9, 2013

### rude man

Also, what is the meaning of "1.z A"?

6. Feb 9, 2013

### TSny

I don't know. Could the "z" be a misprint? EDIT: oops! I thought this question was from the OP.