Electric force with a moving conductive bar in a magnetic field

AI Thread Summary
When a conducting bar moves through a magnetic field, an electric field is induced within the bar. The direction of the electric field can be determined using the right-hand rule, where the thumb represents the direction of the velocity, the index finger the magnetic field, and the resulting electric field direction is indicated by the middle finger. The discussion clarifies that the electric field in this scenario is directed upwards. Misunderstandings about the application of the right-hand rule are addressed, emphasizing the importance of correctly using the two-finger-thumb method for clarity. Understanding these principles is crucial for solving related physics problems effectively.
slain4ever
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Homework Statement


A conducting bar is moved to the right in a magnetic field going into the page, an electric field is set up in the bar. Is this electric field upwards or downwards.

The Attempt at a Solution


i think that because a current is being induced in the bar you use the right hand rule but the current goes the other way in the thumb therefore the electric field is up the bar. Is this correct?
 
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slain4ever said:

Homework Statement


A conducting bar is moved to the right in a magnetic field going into the page, an electric field is set up in the bar. Is this electric field upwards or downwards.

The Attempt at a Solution


i think that because a current is being induced in the bar you use the right hand rule but the current goes the other way in the thumb therefore the electric field is up the bar. Is this correct?
The electric field is given by:

\vec{E} = \vec{v} \times \vec{B}

So use the right hand rule for cross product (use the index finger for v and the middle finger for B and the thumb will give the direction of E).

AM
 
is that a yes, by the way i think you misunderstood, i use the right hand palm rule, not the flemming thing.
 
slain4ever said:
is that a yes, by the way i think you misunderstood, i use the right hand palm rule, not the flemming thing.
If you use the right hand two-finger-thumb rule to determine cross product, you will not be confused.

AM
 
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