How Does the Time Derivative of Electric Field Cross with Magnetic Field?

AI Thread Summary
The discussion centers on the cross product of the time derivative of the electric field and the magnetic field, expressed as ∂E/∂t × B. Participants emphasize the importance of knowing the explicit forms of E and B for accurate calculations. The product rule for derivatives is highlighted, stating that d/dt(E × B) = dE/dt × B + E × dB/dt. A suggestion is made to utilize the determinant form of the cross product for simplification. Overall, the conversation focuses on the mathematical approach to developing the cross product in a Cartesian coordinate system.
gjfelix2006
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Hi, my question is the following:

<br /> \frac{\delta\vec E}{\delta t}\times \vec B = ?<br />
In other words, how can i develop this cross product.
Are there any identity that reduces this product?
Thanks.
 
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Do you have E as a function of time? What coordinate system are you taking the cross product in?
 
of course E is a function of time, and i think for simplicity the coordinate system is cartesian. Thanks
 
There is the product rule d/dt(E x B) = dE/dt x B + E x dB/dt. That's about all I can tell you unless you give us what E and B are explicitly (which is what I think berkeman was asking).
 
gjfelix2006 said:
of course E is a function of time, and i think for simplicity the coordinate system is cartesian. Thanks
Fair enough. Take the derivative and use the determinant form of the cross product. That should get you what you need.

http://en.wikipedia.org/wiki/Cross_product
 
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