# Direction of induced currents

• ellieee

#### ellieee

Homework Statement
would there be induced current in rods PQ and RS?
Relevant Equations
nil
I don't understand why they said that the induced current flow is opposite to each other when it clearly states direction is to the right for both? https://www.physicsforums.com/attachments/285900

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• 16261850189355184978004148639225.jpg
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It's not quite clear (what is the experiment that is repeated?), but I think it means that if you consider the circuit formed by the rods and rails, the induced current in PQ is clockwise, and that in RS is anticlockwise, i.e. the opposite direction around the circuit, so there is no net current in the circuit.

rsk
Imagine a circuit where the current along the top line is L-R and the current along the bottom line is also L-R. It can't happen, because the current needs to flow around the circuit so must flow in the opposite direction in the top and bottom of the circuit.

So, in this case, the emf induced in each rod is in the same direction, so there can be no current because the emfs are cancelling each other out (like connecting two batteries facing each other) so the total emf in the circuit is zero.