Q. Consider the following statements:
Statement I:
Scientific studies suggest that a shift is taking place in the Earth’s rotation and axis.
Statement II:
Solar flares and associated coronal mass ejections bombarded the Earth’s outermost atmosphere with a tremendous amount of energy.
Statement III:
As the Earth’s polar ice melts, the water tends to move towards the equator.
Which one of the following is correct in respect of the above statements?
(a) Both Statements II and III are correct and both of them explain Statement I
(b) Both Statement II and Statement III are correct but only one of them explains Statement I
(c) Only one of the Statement II and III is correct and that explains Statement I
(d) Neither Statement II nor Statement III is correct
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Answer & Explanation:
✅Correct Answer: (b) Both Statement II and Statement III are correct but only one of them explains Statement I
Explanation:
Statement I – Correct
Scientific studies, including NASA-funded research based on more than 120 years of observational data, indicate that the Earth’s rotation speed and spin axis are gradually changing. This is primarily due to redistribution of Earth’s mass, such as melting ice sheets, groundwater extraction, and sea-level rise, which alter the planet’s moment of inertia and slightly lengthen the duration of a day.
Statement II – Correct (but does NOT explain Statement I)
Solar flares and coronal mass ejections (CMEs) release enormous amounts of energy into Earth’s upper atmosphere, causing phenomena like auroras, ionospheric disturbances, and thermospheric expansion. However, this energy is largely absorbed or deflected by Earth’s magnetic field and does not produce any significant or long-term effect on Earth’s rotation or axis.
Statement III – Correct (and explains Statement I)
When polar ice melts, the resulting water flows toward lower latitudes, especially the equatorial region. This redistribution of mass changes Earth’s moment of inertia, leading to a shift in the spin axis and a slight slowing of rotation. This process directly explains the changes mentioned in Statement I.
Why Other Options Are Incorrect
- Option (a) is incorrect because Statement II does not explain Statement I.
- Option (c) is incorrect because both Statements II and III are factually correct.
- Option (d) is incorrect because Statements II and III are both correct.