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Direction of induced EMF in loop

  • Thread starter iharuyuki
  • Start date
  • #1
17
1

Homework Statement


upload_2015-4-14_14-46-44.png


Homework Equations



Faraday's and Lenz' law.

emf = -d(ф)/dt

The Attempt at a Solution


The current is increasing upwards during that time interval.
Thus, by Right-Hand-Rule, the magnetic field goes into the page at the loop.
Lenz' law says that the loop's induced emf will produce a magnetic field that opposes the field from the wire.
Thus a magnetic field in the opposite direction, out of page, would mean, by RHR, that the induced emf is counter-clockwise.

This is however not the answer. Which one of the above statements is flawed?

Thank you very much.
 

Answers and Replies

  • #2
528
33
Draw the graph of sin2πt and check if it increases from 0.25 to 0.3
 
  • #3
17
1
Oh I understand that it decreases actually. I had only punched sin (2pi(0.28)) into a calculator and it gave me a positive. Thank you.
 

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