The Left-Hand Rule is used to determine the direction of current in which phenomenon?

The Left-Hand Rule is used to determine the direction of current in which phenomenon?

• A. Magnetic resonance
• B. Electromagnetic induction
• C. Thermal conduction
• D. Sound propagation

Answer: (B)

The Left-Hand Rule is about the motor effect: how a current-carrying conductor behaves in a magnetic field to produce motion. Using Fleming’s Left-Hand Rule, the forefinger points in the direction of the magnetic field, the middle finger points in the direction of conventional current, and the thumb points in the direction of the force (the motion) on the conductor. This rule helps determine how the conductor will move in a given magnetic setup, which is why it’s used for electric motors. Importantly, to find the direction of induced current in electromagnetic induction, the Right-Hand Rule is used, not the left-hand version. The other listed phenomena—magnetic resonance, thermal conduction, and sound propagation—do not involve the current–field–force relationship described by this rule. So, the left-hand rule best explains the motor effect, where current in a magnetic field produces a force and thus motion; it does not directly determine current direction in electromagnetic induction.

The Left-Hand Rule is about the motor effect: how a current-carrying conductor behaves in a magnetic field to produce motion. Using Fleming’s Left-Hand Rule, the forefinger points in the direction of the magnetic field, the middle finger points in the direction of conventional current, and the thumb points in the direction of the force (the motion) on the conductor. This rule helps determine how the conductor will move in a given magnetic setup, which is why it’s used for electric motors.

Importantly, to find the direction of induced current in electromagnetic induction, the Right-Hand Rule is used, not the left-hand version. The other listed phenomena—magnetic resonance, thermal conduction, and sound propagation—do not involve the current–field–force relationship described by this rule.

So, the left-hand rule best explains the motor effect, where current in a magnetic field produces a force and thus motion; it does not directly determine current direction in electromagnetic induction.