# Homework Help: Magnetic dipole moment

1. Feb 12, 2012

### jonathng

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

A wire is bent into the shape shown in the figure. The semi-circular part has a radius r = 4.00 cm and the rectangular part has a width w = 1.00 cm. A current of 0.300 A runs through the loop. What is the magnitude of the magnetic moment of the loop?

Note: The figure shows a semicircle with a small rectangle at the bottom. Making the rectangle 1cm by 8cm.

2. Relevant equations

u=NIA
Area of a circle
A=lw

3. The attempt at a solution

I have plugged in the values given and added the area of a rectangle to half the area of the circle, and I used one for the amount of loops.
So u=(1)(0.300)((.04^2 pi x0.5)+(.01x.08)

The answer I am getting is 9.9398e-4 which is incorrect. Any help is appreciated! Thanks!
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution