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Activities/Turtle Art/Using Turtle Art Sensors (view source)
Revision as of 02:48, 4 February 2011
, 02:48, 4 February 2011→Ampere's Law
In the special case of a wire in free space, the integral is easy to evaluate. At a radius r, the field is uniform over a circular path round the wire , the path length is 2πr. So for the magnetic field B at a radius r from a wire in free space, [[File:B2Pir-equals-uoI.jpg]]
In the special case of a wire in free space, the integral is easy to evaluate. At a radius r, the field is uniform over a circular path round the wire , the path length is 2πr. So for the magnetic field B at a radius r from a wire in free space, [[File:B2Pir-equals-uoI.jpg]]
[[File:Circular-field.jpg]]