IGCSE: Wire carrying a current in a magnetic field

AI Thread Summary
The discussion centers on a physics problem involving two wires carrying current in a magnetic field, where one wire is flexible and the other is rigid. The user initially believes that since both wires carry current in the same direction, they should repel each other. However, the marking scheme indicates that the flexible wire moves toward the rigid wire. The confusion arises from the interaction of the magnetic fields generated by the currents, which can attract rather than repel when the currents are aligned. The user seeks clarification on the marking scheme's accuracy regarding this phenomenon.
Peter G.
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Basically there is a cardboard with a small hole for a wire and a large circular hole for another wire. Two wires, one rigid is passed through the small hole and another flexible wire is passed through the large circular hole. A battery is connected to both ends of both wires so that the current flows down in both wires. Then, it asks me in what direction will the flexible wire (in the large circular hole) will move to.

I thought that, since the current is flowing down (in the same direction) in both wires then they would repel each other. But the marking scheme says that the flexible wires moves towards the thick rigid wire.

Could anyone tell me why please?

Thanks,
Peter

P.S (First time using this forum, so I'm not sure if my description of the problem is clear and adequate)
 
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It's clear enough

I thought that, since the current is flowing down (in the same direction) in both wires then they would repel each other.

Based on what rules ?

Is it customary of this forum to explain your attempt of solution. Someone will check it.
 
I didn't understand what you say. I think this is what you mean:

If its customary of this forum to explain solutions... Well I don't know, as I've said, I never used it.

And if you say someone will check it, meaning a teacher, well they are not since I am studying for a test and I'm trying a past paper. I don't have anymore lessons until the day of the test.

Well, I think it is based on the fact that whenever a current is reversed, the field is also reversed. If the current is flowing in the same direction in both wires than they will produce equal magnetic fields that when interact, will repel, not attract.

The reason I put this question here is because I want to know if the marking scheme is possibly wrong. As simple as that. All I need is basically a Yes, you are right, or a no. People don't even need to explain what I got wrong if people don't want to, I will simply research myself if that's the case
 
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