Fleming’s Left-Hand Rule is a mnemonic and a visualization technique used to determine the direction of the force experienced by a current-carrying conductor placed in a magnetic field. This rule is applicable to scenarios where the current, magnetic field, and force are mutually perpendicular.

The rule is named after Sir John Ambrose Fleming, a British electrical engineer and physicist. Here’s how Fleming’s Left-Hand Rule is applied:

  1. Thumb (First Finger): Point your thumb in the direction of the motion of the Conductor (current).
  2. First Finger (Index Finger): Point your index finger in the direction of the magnetic Field.
  3. Second Finger (Middle Finger): Extend your middle finger in the direction of the Force.

The key is to remember the three directions: Thumb for current (motion of the conductor), Index finger for the magnetic field, and Middle finger for the force.

Here’s a summary:

  • Finger directions:
    • Thumb: Current (I)
    • Index finger: Magnetic Field (B)
    • Middle finger: Force (F)
  • Application:
    • If you point your thumb in the direction of the current, your index finger in the direction of the magnetic field, your middle finger will naturally point in the direction of the force experienced by the conductor.
  • Symbolic Representation:
    • F⃗F

(Force) is perpendicular to both B⃗B (Magnetic Field) and I⃗I

    • (Current).

This rule is commonly used in physics and electrical engineering to understand the interactions between current-carrying conductors and magnetic fields. It’s particularly relevant in scenarios involving electric motors, generators, and other devices where the interaction between magnetic fields and currents produces mechanical forces.

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