Final answer:
To determine the magnitude and direction of the magnetic field at a point 0.1 meters away from an infinitely long wire carrying a current of 125 A, you can use the right-hand rule. The magnitude of the magnetic field can be calculated using the formula B = μ0 * i / (2π * r), where B is the magnitude of the field, μ0 is the permeability of free space, i is the current, and r is the distance from the wire.
Step-by-step explanation:
To determine the magnitude and direction of the magnetic field at a point 0.1 meters away from an infinitely long wire that carries a current of 125 A, we can use the right-hand rule. According to the right-hand rule, if you point your right thumb in the direction of the current, your curled fingers will indicate the direction of the magnetic field.
Since the wire is infinitely long, we can consider it to be a straight wire. The magnitude of the magnetic field around a straight wire is given by the formula:
B = μ0 * i / (2π * r)
\where B is the magnitude of the magnetic field, μ0 is the permeability of free space (4π x 10-7 Tm/A), i is the current in the wire (125 A), and r is the distance from the wire (0.1 m).
Plugging in the values, we get:
B = (4π x 10-7 Tm/A) * (125 A) / (2π * 0.1 m) = 2 x 10-4 T
Therefore, the magnitude of the magnetic field at a point 0.1 meters away from the wire is 2 x 10-4 T. The direction of the magnetic field can be determined using the right-hand rule, pointing the thumb in the direction of the current.