The strength of the earth's magnetic field varies from place to place on the earth's surface; its value being of the order of ___________.

The correct answer is 10-5 T.

Key Points

• The strength of the Earth's magnetic field, also known as the geomagnetic field, varies from place to place on the Earth's surface.
• Its value is typically of the order of 10-5 Tesla (T) or 25 to 65 microteslas (0.25 to 0.65 Gauss).
• The geomagnetic field is mainly generated by the motion of molten iron alloys in the Earth's outer core.
• This field plays a crucial role in protecting the Earth from the solar wind and cosmic radiation.

Additional Information

• Magnetic Field Measurement
  • The unit of magnetic field strength is the Tesla (T), which is equivalent to one weber per square meter.
  • Another common unit used is the Gauss (G), where 1 Tesla equals 10,000 Gauss.
• Magnetosphere
  • The Earth's magnetic field extends from the Earth's interior out into space, where it interacts with the solar wind.
  • This region, called the magnetosphere, deflects most of the solar wind, which protects the atmosphere from being stripped away.
• Geomagnetic Poles
  • The Earth's magnetic field has two poles: the North Magnetic Pole and the South Magnetic Pole.
  • These poles are not fixed and can migrate due to changes in the Earth's core and external influences.
• Magnetic Field Reversals
  • Over geological time scales, the Earth's magnetic field has reversed its polarity many times.These reversals, known as geomagnetic reversals, occur on average every few hundred thousand years.