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DavidD
So there is charged ball, say with negative charge (like electron). This ball charge say is 1 Coloumb and mass 1 kg. This charged ball rotates about his axis with speed 1000 m/s. What will be strenght of magnetic field? And where will be North pole and where - South pole?
My assumption is that in center there will be South pole and closer to surface and on surface there will be North pole. Right?
Say this axis is on Earth and rotates in same direction in which clock going...(this is actauly don't interesting for, but rather where will be poles, what shape...)

My thinking direction is such: there is angular speed aceleration and thus it's like from center to surface charge moving. And also I would like to ask, does such rotating ball will radiate electromagnetic waves (becouse of icentric accelration)?
DavidD
A little bit correction. Ball radius is 0.1 m. And rotation speed is surface of line, "which rotates at biggest speed" - you know what I mean, like earth in some places have bigger angular velocity than in over, so there is in "center" the bigest angular velcoity, which in my case is 1000 m/s. But seems, that nobody know answers to my questions. Where are you physics? You should know this!

And btw, south pole I think must be in center and like cylind, through which going axis and this axis connecting two cilindr oval surfeaces...
Also I think that possible such ball even don't have magnetic properties or/and don't radiating electromagnetic waves.
gabba gabba hey
QUOTE (DavidD+Jul 6 2008, 04:33 PM)
So there is charged ball, say with negative charge (like electron). This ball charge say is 1 Coloumb and mass 1 kg. This charged ball rotates about his axis with speed 1000 m/s. What will be strenght of magnetic field? And where will be North pole and where - South pole?
My assumption is that in center there will be South pole and closer to surface and on surface there will be North pole. Right?
Say this axis is on Earth and rotates in same direction in which clock going...(this is actauly don't interesting for, but rather where will be poles, what shape...)

My thinking direction is such: there is angular speed aceleration and thus it's like from center to surface charge moving. And also I would like to ask, does such rotating ball will radiate electromagnetic waves (becouse of icentric accelration)?

The strength of the magnetic field would depend on the material the ball is made of, and more specifically how the charge is distributed throughout the ball. For example, the ball could be made of a very good conductor like copper, in which case the charge would be evenly distributed along the surface of the ball and the field would be easy to calculate.

As for the location of the poles, if the ball is assumed to be spherical, the only information u need to provide is which direction it spins. If it is spinning counterclockwise, The north pole will be at the top of the ball (one end of the axis) and the south pole will be at the bottom (the other end of the axis) and vice versa if it spins clockwise.
DavidD
QUOTE (gabba gabba hey+Aug 14 2008, 02:53 AM)
The strength of the magnetic field would depend on the material the ball is made of, and more specifically how the charge is distributed throughout the ball. For example, the ball could be made of a very good conductor like copper, in which case the charge would be evenly distributed along the surface of the ball and the field would be easy to calculate.

As for the location of the poles, if the ball is assumed to be spherical, the only information u need to provide is which direction it spins. If it is spinning counterclockwise, The north pole will be at the top of the ball (one end of the axis) and the south pole will be at the bottom (the other end of the axis) and vice versa if it spins clockwise.

Yeah, I ask this when don't know about magnetism good... Magnetic field will be along axis...
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