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gjfelix2006
Aug1-06, 04:05 PM
Hi, my question is the following:


\frac{\delta\vec E}{\delta t}\times \vec B = ?

In other words, how can i develop this cross product.
Are there any identity that reduces this product?
Thanks.

berkeman
Aug1-06, 04:42 PM
Do you have E as a function of time? What coordinate system are you taking the cross product in?

gjfelix2006
Aug1-06, 07:17 PM
of course E is a function of time, and i think for simplicity the coordinate system is cartesian. Thanks

StatusX
Aug1-06, 07:40 PM
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).

berkeman
Aug1-06, 07:43 PM
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