Increasing the current flowing through a conductor will ? the strength of the electromagnetic field around that conductor.

Increasing the current flowing through a conductor will ? the strength of the electromagnetic field around that conductor.

• A. Cause no change to
• B. Decrease
• C. Increase
• D. Depends on resistance

Answer: (C)

Increasing the current through a conductor strengthens the magnetic field around it. The magnetic field produced by a current is proportional to the amount of current. For a long straight wire, the field strength is B = μ0 I /(2π r), so when I goes up, B goes up in direct proportion. The field is set by how much charge is moving, not by the wire’s resistance; resistance only influences the current for a given voltage (I = V/R). So, increasing the current directly increases the magnetic field. The field lines circle the wire, with direction given by the right-hand rule.

Increasing the current through a conductor strengthens the magnetic field around it. The magnetic field produced by a current is proportional to the amount of current. For a long straight wire, the field strength is B = μ0 I /(2π r), so when I goes up, B goes up in direct proportion. The field is set by how much charge is moving, not by the wire’s resistance; resistance only influences the current for a given voltage (I = V/R). So, increasing the current directly increases the magnetic field. The field lines circle the wire, with direction given by the right-hand rule.