I too find Lenz's law somewhat confusing haha.
If I remember correctly, moving the south pole of a magnet into a coil "decreases" the number of magnetic field lines going through the coil, hence a decrease in flux.
Below is a picture that sorta explains it (sorry about my horrible hand writing and drawing)
I personally find anything to do with the south pole of the magnet in relation to the coil rather confusing, however I understand when it is just the north pole and coil.
As you can see,
number 1 and
number 3 have the same induced current direction.
Also,
number 2 and
number 3 have the same induced current direction.
Scenario 1North pole of magnet moving into coil.
Number of magnetic fields in the coil increase (flux increases) from 2 -> 4 (To the
right). Thus using a variant of the RHGR you can see that the opposing flux will counteract this change by reducing the flux in coil (Lets say, 2 field lines to the left). As a result the induced current will be anti clockwise when looking from the viewpoint of "1".
Scenario 2North pole of magnet moving out of coil.
The amount of flux decreases from 4 -> 2 (To the
right). Thus using the RHGR you will realise that the current induced will be in the opposite direction to that of scenario one, as flux need to be "added" to oppose the change.
Scenario 3South pole of magnet moving into coil
The amount of flux decreases from 4 -> 2 (To the
right). The explanation would be the same as scenario 2.
Scenario 4South pole of magnet moving out of coil
Flux decreases from 2 -> 4 (To the
right). It would be the same explanation as scenario 1.
Sorry if I didn't explain things properly, as it's pretty hard to explain it just solely using words - It would be much easier to explain it like my teacher did, with a coil and his hand
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