Question

The geomagnetic field present on the Earth protects our planet from:

• A. thermal power radiation hazards
• B. nuclear radiation hazards
• C. seismic radiation hazards
• D. cosmic radiation hazards

Hint:

The geomagnetic field = Earth’s invisible shield against cosmic and solar radiation.

Answer 1

The Correct Option is D

To understand how Earth's geomagnetic field protects our planet, we need to examine its interaction with various types of radiation from space.

1. Nature of Earth's Magnetic Field:
The Earth generates a powerful magnetic field that extends far into space, creating a protective region called the magnetosphere. This field is produced by the motion of molten iron in Earth's outer core.

2. Protection Mechanism:
The geomagnetic field primarily deflects charged particles from:

- Solar wind (continuous stream of charged particles from the Sun)
- Cosmic rays (high-energy particles from outer space)
These particles would otherwise strip away our atmosphere and bombard the surface with harmful radiation.

3. Types of Radiation Blocked:
While the magnetic field doesn't directly block:
- Thermal radiation (dealt with by the atmosphere)
- Nuclear radiation (localized human-made hazard)
- Seismic waves (completely unrelated to magnetism)
It is exceptionally effective against cosmic radiation, which consists of high-energy charged particles.

4. Scientific Evidence:
Studies show:

- Mars (with no global magnetic field) lost most of its atmosphere to solar wind
- Astronauts in space receive much higher radiation doses than on Earth
- The Van Allen belts (trapped charged particles) demonstrate this protective effect

Final Answer:
The geomagnetic field protects Earth from $\boxed{\text{cosmic radiation hazards}}$.