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“The magnetic field arises due to electric current produced by convective motion of metallic fluids in the outer core of the earth.” This statement is known as

“The magnetic field arises due to electric current produced by convective motion of metallic fluids in the outer core of the earth.” This statement is known as Correct Answer Dynamo Effect

CONCEPT:

The Dynamo effect:

  • It is a theory that explains the origin of the Earth's main magnetism in terms of a self-sustaining dynamo.
  • In this dynamo mechanism, fluid motion in the Earth's outer core moves conducting material (liquid iron) across an already existing, weak magnetic field and generates an electric current.
  • The electric current, in turn, produces a magnetic field that also interacts with the fluid motion to create a secondary magnetic field.
  • Together, the two fields are stronger than the original and lie essentially along the axis of the Earth's rotation.

EXPLANATION:

  • From the above, it is clear that the electric current produced by the convective motion of metallic fluid in the outer core of the earth is known as the Dynamo effect.

Additional Information

Seeback effect:

  • If two different metal wires are joined to form a closed circuit and two junctions are kept at different temperatures, a small emf is set up in the circuit in a definite direction. This effect is called a thermoelectric effect or Seebeck effect.
    • The emf developed in the circuit is called thermal emf or Seeback emf and the current called thermoelectric current.

Thomson Effect:

  • Thomson effect is the evolution or absorption of heat when an electric current passes through a circuit composed of a single material that has a temperature difference along its length.

Meissner’s effect: 

  • It is defined as the effect of the repulsion of magnetic flux when it placed in an external magnetic field.

Related Questions

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