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Just like the Astronomy Q&A game in the Astronomy forum, let's play a physics Q&A game here. The astronomy game has certainly taught me some very neat facts -- maybe this one will do the same.
I'm going to post one question posed by marcus:
"A favorite version of the question chroot just answered is the one about the airplane flying the polar route. It is going 200 meters per second and its wingspan is 30 meters----what is the voltage difference between the two wingtips? I am not asking this question because it is a cousin of the one asked by Ivan, just recalling it. the plane is in a region where the Earth's magn. field is roughly vertical and of such and such a strength etc etc."
It seems that there should be no voltage. Faraday's law dictates that
E = -N d[phi]/dt
Since [phi] is defined as the flux: [phi] = B * A, where B is the magnitude of the magnetic field and A is the area enclosed by the loop. In this problem, neither A nor B is changing -- so the induced voltage should be zero.
Am I right? Was it really just a trick question?
- Warren
I'm going to post one question posed by marcus:
"A favorite version of the question chroot just answered is the one about the airplane flying the polar route. It is going 200 meters per second and its wingspan is 30 meters----what is the voltage difference between the two wingtips? I am not asking this question because it is a cousin of the one asked by Ivan, just recalling it. the plane is in a region where the Earth's magn. field is roughly vertical and of such and such a strength etc etc."
It seems that there should be no voltage. Faraday's law dictates that
E = -N d[phi]/dt
Since [phi] is defined as the flux: [phi] = B * A, where B is the magnitude of the magnetic field and A is the area enclosed by the loop. In this problem, neither A nor B is changing -- so the induced voltage should be zero.
Am I right? Was it really just a trick question?
- Warren