Question

The pattern of the magnetic field produced by the straight current carrying conducting wire is:

• A. in the direction opposite to the current
• B. in the direction parallel to the wire
• C. circular around the wire
• D. in the same direction of current

Hint:

Remember Maxwell's Right-Hand Thumb Rule:
Thumb = Direction of current (\(I\)).
Curled Fingers = Direction of magnetic field lines (\(B\)).
The field lines always form concentric closed loops.

Answer 1

The Correct Option is C

Step 1: Understanding the Question:
The question asks for the geometric shape and pattern of the magnetic field lines generated around a long, straight wire carrying a steady electric current.

Step 2: Key Formula or Approach: According to electromagnetism (specifically Oersted's discovery and Biot-Savart Law), current flowing through a straight wire produces a magnetic field that circles the wire.
The direction of these magnetic field lines is determined by Maxwell's Right-Hand Thumb Rule.

Step 3: Detailed Explanation:

• When an electric current flows through a straight conductor, magnetic field lines are created in the space surrounding the conductor.

• Iron filing experiments show that these magnetic field lines form concentric circles centered on the wire.

• The plane containing these concentric circular lines is perpendicular to the straight conducting wire.

• If you point the thumb of your right hand in the direction of the current, the curl of your fingers gives the direction of these circular magnetic field lines (clockwise or counter-clockwise).

• These field lines do not intersect and their density is higher near the wire, representing a stronger magnetic field closer to the current source.


Step 4: Final Answer:
Thus, the pattern of the magnetic field lines is circular around the wire.