Troublesome problem with finding the electric current

Oct 2019
In this problem we have A wire with resistance per unit length of 32 Ω/m that is bent at a right angle. The second straight fragment of the same wire (The blue one) moves at the top of the first one at a speed of v = 4 m/s. The whole system is located in a magnetic field with an induction of B = 8 T, perpendicular to the wires (as in the picture). What we need to do is to find the current flowing through the wires.

We can Ignore the resistance at the points of contact of both wires and also the magnetic field generated by the current itself that is taken into consideration.

So these are two distinct wires that are identical, but separate


Last edited:
Jun 2016
As you point out this is a badly presented problem
there are at least two seemingly equally plausible ways of interpreting the problem.

Is there any clue to be obtained from the wider context of the problem,
for example additional information in preceding (or even following) questions.
or perhaps even looking at the wider context of the section of the text book from which the problem has been lifted?
Oct 2019
I think It is the more regular type of "conundrum" - we have two electrical conductors (in this case wires) that are made of the same things, etc - they're of the same nature, but they are not connected to each other. One other Thing that makes me think is the way the wire slides at the top of the bent one - not quite sure if they do indeed come in contact, or is this somehow negated by the emf, from the electromagnetic field.