Geomagnetism is the scientific study of Earth’s magnetic field and its influence on our planet. This captivating field of research delves into the origin, behaviour, and changes of the Earth’s magnetic forces, shedding light on phenomena like magnetic declination, auroras, and even past magnetic reversals. From the magnetic poles to the magnetosphere, Geomagnetism unravels the mysteries of our planet’s invisible shield.
Some important multiple-choice questions related to this topic are listed below. Try to answer these questions after reading enough in this topic. Also tie your answer with the given one. This practice may help you sharpen your preparation for any competitive exam along with increase your knowledge in this topic.
1. What causes Earth’s magnetic field?
(A) Solar radiation
(B) Earth’s rotation
(C) Tectonic plate movements
(D) Geothermal energy
2. The region where the Earth’s magnetic field lines converge is called the:
(A) Magnetopause
(B) Magnetosphere
(C) Magnetic equator
(D) Magnetic poles
3. Which of the following materials is not commonly used in the construction of a magnetometer?
(A) Barium ferrite
(B) Superconducting wire
(C) Fluxgate sensors
(D) Aluminium foil
4. What unit is used to measure the strength of a magnetic field?
(A) Ampere
(B) Coulomb
(C) Tesla
(D) Weber
5. The phenomenon in which Earth’s magnetic field reverses direction over time is called:
(A) Magnetic declination
(B) Magnetic inclination
(C) Magnetic reversal
(D) Magnetic induction
6. What is the approximate inclination angle of Earth’s magnetic field at the magnetic poles?
(A) 0 degrees
(B) 45 degrees
(C) 60 degrees
(D) 90 degrees
7. The study of how the Earth’s magnetic field has changed over time is known as:
(A) Palaeomagnetism
(B) Geodesy
(C) Seismology
(D) Petrology
8. What is the primary source of Earth’s magnetic field?
(A) Molten iron in the outer core
(B) Ocean currents
(C) Radioactive decay in the mantle
(D) Lightning discharges
9. What is the name of the boundary between Earth’s core and mantle, where the magnetic field is generated?
(A) Asthenosphere
(B) Moho discontinuity
(C) D” layer
(D) Outer core-inner core boundary
10. Which instrument is commonly used to measure changes in the Earth’s magnetic field?
(A) Gravimeter
(B) Magnetometer
(C) Spectrometer
(D) Seismograph
11. What is the name of the line connecting points on the Earth’s surface where the magnetic field is horizontal?
(A) Isoclinic line
(B) Isogonic line
(C) Isothermal line
(D) Isobaric line
12. What is the term for the deviation between true north and magnetic north?
(A) Magnetic inclination
(B) Magnetic reversal
(C) Magnetic declination
(D) Magnetic induction
13. Which instrument is used to measure the strength and direction of the Earth’s magnetic field?
(A) Seismograph
(B) Barometer
(C) Magnetometer
(D) Anemometer
14. The region where the Earth’s magnetic field interacts with the solar wind is known as the:
(A) Magnetopause
(B) Magnetosphere
(C) Magnetic equator
(D) Magneto sheath
15. What causes the auroras (Northern and Southern Lights) in Earth’s atmosphere?
(A) Solar wind particles interacting with the magnetosphere
(B) Lightning discharges in the ionosphere
(C) Geothermal activity near the Earth’s surface
(D) Volcanic eruptions releasing charged particles
