Voltage induced by changing field

AI Thread Summary
The discussion focuses on calculating the voltage across a 30-turn wire loop with a diameter of 14 cm and a resistance of 4 ohms, subjected to a varying magnetic field described by the equation B(t) = 4t^3 - 9t^2 + 3t - 28. Participants seek to determine the voltage at t = 2 seconds, the resulting current, and the direction of the induced current. There is uncertainty regarding the explanation for the direction of the induced current and whether the magnetic flux is increasing or decreasing at that time. The conversation emphasizes the need for clarity in understanding electromagnetic induction principles. Overall, the thread highlights the importance of applying Faraday's law to solve the problem effectively.
Cyan Ray
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5. A wire is formed into a 30 turn loop whose diameter is 14 cm and the resistance of the loop is 4 ohmns. The loop is placed on this page and a magnetic is going directly into the plane of the paper and is varying according to the formula
B(t) = 4t^3 - 9t^2 + 3t - 28

Part (a): What is the voltage across the loop at t = 2s?
Part (b): What is the current in the loop at this time?
Part (c): What is the direction of the induced current? Explain
Here is my solution
 

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Is this right?

And as for c) I have no explanation...what is an approriate explanation?
 
Cyan Ray said:
And as for c) I have no explanation...what is an approriate explanation?
Is the flux increasing or decreasing at t = 2s? :smile:
 

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