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**[SOLVED] EMF problem - Current in Coil**

**1. Homework Statement**

A small square coil is located inside an ideal solenoid at the center with its plane oriented perpendicular to the axis of the solenoid. The resistance of this coil is 2.00 [tex]\Omega[/tex] and each side is 4.00 cm long. The solenoid has 125 windings per centimeter of length. If the current in the solenoid is increasing at a constant rate of 1.50 A/s, the current in the square coil is:

a) steady at 18.8 [tex]\mu A[/tex]

b) initially equal at 18.8 [tex]\mu A[/tex] but is increasing

c) increasing at 1.50 A/s

d) decreasing at 1.50 A/s

e) zero

**2. Homework Equations**

[tex]\epsilon=\frac{d\Phi_{B}}{dt}[/tex]

[tex]

\Phi_{B}=BA

[/tex]

**3. The Attempt at a Solution**

First, I plugged in what I know for magnetic flux:

[tex]\Phi_{B}=BA=B(.04 m^{2})[/tex]

Then I used that information to plug into the induced emf formula:

And since

[tex]B=\frac{N}{L}*i*\mu_{0}[/tex]

Then

[tex]\epsilon=\left|.04 m^{2}*\frac{N}{L}*\mu_{0}*\frac{di}{dt}\right|[/tex]

where

[tex]\frac{di}{dt}[/tex] is 1.5 A/S

N = (125 *.04 m) = 5

**

My question is, am I going about this the right way? And if so, How do I find L and how can I use that to eventually get to the induced current?