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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.

the minimum amperage that the current in this wire would have to have so that its weight is completely supported by the magnetic force due to earth's field, assuming that no other forces except gravity act on it

jupiter is the largest planet in our solar system, having a mass and radius that are respectively, 318 and 11.2 times that of earth. suppose that an object falls from rest near the surface of each planet and that the acceleration due to gravity remains constant during the fall. each object falls the same distance before striking the ground. determine the ratio of the time of fall on jupiter to that on earth.