If a copper rod carries a direct current, the magnetic field associated with the current will be?
Show Hint
- Parallel to the rod
- Perpendicular to the rod
- Circular around the rod
- No magnetic field
The Correct Option is C
Solution and Explanation
When a current flows through a straight conductor, such as a copper rod, a magnetic field is produced around it.
This is described by Ampere’s Circuital Law, which states: \[ \oint B \cdot dl = \mu_0 I, \] where: \( B \) is the magnetic field, \( \mu_0 \) is the permeability of free space, \( I \) is the current flowing through the conductor.
The field lines form concentric circles around the conductor, with the direction given by the right-hand rule: Point your thumb in the direction of the current.
The curl of your fingers gives the direction of the magnetic field.
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