# Square Coil, Round Hole

1. Aug 17, 2007

### KidA

1. The problem statement, all variables and given/known data
A square, single-turn wire coil L = 1.13 cm on a side is placed inside a solenoid that has a circular cross section of radius r = 2.77 cm, as shown in the figure below.

Basically a big circle with a square in the center.

The solenoid is 20.0 cm long and wound with 149 turns of wire. If the current in the solenoid is 3.29 A, find the flux through the coil.

2. Relevant equations

3. The attempt at a solution
I was thinking that this was a problem dealing with mutual inductance, but there isn't an equation that will give me the variable I need.
Є=-(ΔNΔΦ/Δt)
I don't know the induced emf (Є), and there isn't any change in time (Δt)
The equation for finding the flux doesn't help either:
Φ=BAcosΘ
I don't know the strength of the magnetic field (B). I really don't know what else to add. I've searched my book and pondered over every equation trying to find some way to solve this. I hope I don't piss anyone off due to lack of information, but this is my first time on this forum.

Any help/feedback would be greatly appreciated. Thanks.

2. Aug 17, 2007

### Staff: Mentor

There's your problem. You should know how to find the field inside a solenoid.

3. Aug 17, 2007

### KidA

Ahhh, I should have known that. Thank you very much.