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ttiger2k7
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[SOLVED] EMF problem - Current in Coil
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 \Omega 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 \mu A
b) initially equal at 18.8 \mu A but is increasing
c) increasing at 1.50 A/s
d) decreasing at 1.50 A/s
e) zero
\epsilon=\frac{d\Phi_{B}}{dt}
<br /> \Phi_{B}=BA<br />
First, I plugged in what I know for magnetic flux:
\Phi_{B}=BA=B(.04 m^{2})
Then I used that information to plug into the induced emf formula:
And since
B=\frac{N}{L}*i*\mu_{0}
Then
\epsilon=\left|.04 m^{2}*\frac{N}{L}*\mu_{0}*\frac{di}{dt}\right|
where
\frac{di}{dt} 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?
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 \Omega 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 \mu A
b) initially equal at 18.8 \mu A but is increasing
c) increasing at 1.50 A/s
d) decreasing at 1.50 A/s
e) zero
Homework Equations
\epsilon=\frac{d\Phi_{B}}{dt}
<br /> \Phi_{B}=BA<br />
The Attempt at a Solution
First, I plugged in what I know for magnetic flux:
\Phi_{B}=BA=B(.04 m^{2})
Then I used that information to plug into the induced emf formula:
And since
B=\frac{N}{L}*i*\mu_{0}
Then
\epsilon=\left|.04 m^{2}*\frac{N}{L}*\mu_{0}*\frac{di}{dt}\right|
where
\frac{di}{dt} 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?
