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Direction of Current Flow in Pivoted Wire Swing Question

In which direction in the diagrams will the pivoted wire swing as current flows through it in the direction indicated? Show clearly with arrow in the diagrams.

Screen Shot 2016-05-27 at 10.12.46 PM.png

I don't understand this question at all and I desperately need help for my physics exam please :smile:
Original post by electrx
In which direction in the diagrams will the pivoted wire swing as current flows through it in the direction indicated? Show clearly with arrow in the diagrams.

Screen Shot 2016-05-27 at 10.12.46 PM.png

I don't understand this question at all and I desperately need help for my physics exam please :smile:


You should apply Fleming's left hand rule. Using your left hand:

1. Arrange your thumb, index finger, and middle finger so that they are at right angles to each other.

2. point your middle finger in the direction of the conventional current i.e. the direction from +ve to -ve

3. point your index finger in the direction of the magnetic field i.e. from N to S.

4. Your thumb is now pointing in the direction of the force felt by the current in the wire.

If you were considering a dynamo or generator, you would do the same thing, but using your right hand. ("geneRIGHTor").

Note that this only works for conventional current, so we have to assume that the direction given in the question is indeed conventional.
(edited 7 years ago)
Reply 2
Original post by atsruser
You should apply Fleming's left hand rule. Using your left hand:

1. point your middle finger in the direction of the conventional current i.e. the direction from +ve to -ve

2. point your index finger in the direction of the magnetic field i.e. from N to S.

3. Your thumb is now pointing in the direction of the force felt by the current in the wire.

If you were considering a dynamo or generator, you would do the same thing, but using your right hand. ("geneRIGHTor":wink:.

Note that this only works for conventional current, so we have to assume that the direction given in the question is indeed conventional.


Got it! Thank you :smile:
Original post by electrx
Got it! Thank you :smile:


Oops! I forgot one rather important point: the three fingers must be at right angles to each other. I guess that you knew that though.

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