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The magnetic field 0.02 m from a wire is 0.1 T. What is the magnitude of the magnetic field 0.01 m from the same wire?

The magnetic field 0.01m from the wire is 0.2T.

Explanation:

The magnetic field at a distance due to a wire carrying current is

Now, let us call the magnetic field at and the magnetic field at :

Dividing by we get

Now we put in the numbers

and to get:

solving for we get:

which is the magnetic field at 0.01 meters from the wire.

c. magnitude and direction