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The book says,

"when a length of copper wire PQ is moved downwards through the poles of two horizontal bar magnets as shown below. Compared to end Q, end P will have fewer electrons."

But isn't it the opposite? Using the left hand rule, for me it seems like the electrons will gather more on the end P - I mean, your thumb points downwards and index finger points right, and the middle finger points backwards which means that the electrons come towards you (the opposite direction to the conventional current).

# Also, would the situation be different if the copper wire is in a loop (continuous?)

Sorry about my horrible handwriting!

  • $\begingroup$ You are right the book is wrong $\endgroup$ Apr 5 '17 at 10:12
  • $\begingroup$ Cannot use left hand rule as it's electromagnetic induction. $\endgroup$ Apr 5 '17 at 10:21

This is the phenomenon of electromagnetic induction, so you cannot use Fleming's left hand rule, you have to use the right hand rule.

Your thumb will point down as conductor moves down, and index finger will point to right. If you do it properly, current will flow from Q to P. So your explanation is correct. So, P has excess of electrons and Q has deficit of electrons.

Please edit left hand to right hand.

Rest is fine.


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