Electromagnetic induction-help with a problem

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The discussion revolves around calculating the potential difference induced in a metal rod moving through a magnetic field. Participants clarify that for electromagnetic induction to occur, the magnetic field must intersect the rod at a right angle, which is not the case here as the field is parallel to the rod's length. The relevant equation for induced emf is confirmed as emf = -BLv, but it is concluded that the induced emf is zero due to the lack of a changing magnetic flux. A rod is defined as a thin cylinder, emphasizing its geometric characteristics. The conversation concludes with acknowledgment of the correct understanding that the induced potential difference is indeed zero.
endeavor
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"A metal rod 20 cm long moves in a straight line at a speed of 4.0 m/s with its length parallel to a uniform magnetic field of 1.2 T. Find the resulting potential difference between the ends of the rod."

I don't know how to solve this...
 
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Did you learn the induced potential equation? (Blv)
also, I'm not sure that I understand the case, the length of the rod is moving through the field and the field is going from one end of the rod to the other? In that case there would be no induction, for there to be induction there has to be a field that makes a right angle with the length of the rod.
 
I mainly learned about loops of wire, not rods...what exactly is a rod? I thought that it's a cylinder...

Oh, is this referring to the metal rod that moves on a metal frame so that the area inside the loop of the frame changes? My book has one example of that, and the equation is emf = -BLv.

If that's the case, then since the flux doesn't change because the field is parallel, then the induced emf is 0.
 
endeavor said:
I mainly learned about loops of wire, not rods...what exactly is a rod? I thought that it's a cylinder...

Oh, is this referring to the metal rod that moves on a metal frame so that the area inside the loop of the frame changes? My book has one example of that, and the equation is emf = -BLv.

If that's the case, then since the flux doesn't change because the field is parallel, then the induced emf is 0.
A rod is basically a thin cylinder, that is a cylinder with a length but no radius. This page may be useful for you... http://www.iop.org/Our_Activities/Schools_and_Colleges/Teaching_Resources/Teaching%20Advanced%20Physics/Fields/Electromagnetism/page_4817.html
Your equation is correct by the way but your conclusions are not :smile:
 
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Hootenanny said:
Your equation is correct by the way but your conclusions are not :smile:
I found out that the answer is 0... but since my conclusions are wrong, I don't know how this answer has been derived. :confused:
 
endeavor said:
I found out that the answer is 0... but since my conclusions are wrong, I don't know how this answer has been derived. :confused:
Ahh my apologies, your conclusion is correct I didn't see the 'parallel' bit :blushing:
 
Hootenanny said:
Ahh my apologies, your conclusion is correct I didn't see the 'parallel' bit :blushing:
Oh Okay, thanks for the help anyway.
 
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