Just follow the direction that the current is flowing in the
coil. Your diagram is already showing the correct directions of
flow. In this case, Current should be pointing "Inwards"
(WHY? Read further), Field to the Right, and there you
have the Force.
Your diagram, although correct in directions, is rather awkward
in portraying the coil. I'll take a better art from Google.
NOTE: Meh, I just realised. You may think that the
rotation of coil is wrong. Rather, if you think so, you're wrong.
The line in the coil "electron motion" actually means the movement
of electrons. If you want the conventional current, you have to
point your Current in the other direction, which is
"Outwards".
Physics is just a matter of using your brain to VISUALISE, isn't
it?
Imagine the first scenario.
Notice how AB and CD shift sides and shift in DIRECTION OF
CURRENT. That's basically the whole point.
Credits to http://student.britannica.com/comptons/art/print?id=53254&articleTypeId=0
for image
Thanks. I'm pretty clear about the part regarding the change in
current direction. However, I'm still unsure as to which part the
finger representing the "current" should point for the question on
D.C motor using Fleming's left-hand rule. It would be good if
you/someone else could explain it to me again.
Thanks again.
