Effect due to which earth's magnetism exist is called

Options

A. a.Dynamo effect
B. b.Core effect
C. c.Corona effect
D. d.Faraday effect

Answer

To determine the effect due to which Earth's magnetism exists, we can analyze the options provided and understand the underlying principles of Earth's magnetic field.

### Step-by-Step Solution:

1. **Understanding Earth's Magnetic Field**:
- The Earth behaves like a giant magnet with a magnetic field that extends from its interior out into space. This magnetic field is primarily attributed to the movement of molten iron and nickel in the Earth's outer core.

2. **Identifying the Options**:
- The options given are:
- Dynamo effect
- Core effect
- Corona effect
- Paradigm effect

3. **Analyzing the Dynamo Effect**:
- The dynamo effect is a geophysical theory that explains how the motion of conductive fluids (like molten iron) generates a magnetic field. As the Earth rotates, the movement of these conducting fluids creates electric currents, which in turn produce a magnetic field.

4. **Examining Other Options**:
- **Core effect**: While it relates to the core, it is not a recognized term in geophysics for explaining Earth's magnetism.
- **Corona effect**: This term is more associated with solar phenomena and not relevant to Earth's magnetic field.
- **Paradigm effect**: This term does not apply to the context of Earth's magnetism.

5. **Conclusion**:
- Given the analysis, the effect due to which Earth's magnetism exists is best described by the **Dynamo Effect**.

### Final Answer:
The effect due to which Earth's magnetism exists is called the **Dynamo Effect**.

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