Change set

Pick exam & year, then Go.

Question map
Not attempted Correct Incorrect Bookmarked
Loading…
Q67 (NDA-I/2022) Science & Technology › Basic Science (Physics, Chemistry, Biology) › Astronomy and astrophysics Answer Verified

Inhabitants are unaware of the speed of rotation of the planet Earth because 1. the angular velocity is constant for each place on the Earth’s surface 2. the atmosphere rotates with the Earth 3. there are no nearby objects, either stationary or moving at a rate different from that of the Earth Which of the above is/are the correct explanation(s)?

Result
Your answer:  ·  Correct: D
Explanation

Inhabitants do not perceive Earth's rotation due to several physical factors. First, the Earth rotates at a constant angular velocity [1]. Human senses are designed to detect changes in velocity (acceleration) rather than uniform motion; since the rotation is smooth and consistent, it remains imperceptible [1]. Second, the atmosphere is not stationary; it rotates along with the Earth's surface due to gravity and friction [2]. This lack of relative motion between the observer and the surrounding air prevents the sensation of movement. Third, the principle of reference frames dictates that motion is perceived relative to other objects [1]. Because all nearby objects—including buildings, trees, and the atmosphere—move at the same rate as the observer, there are no stationary external reference points to provide a visual or physical sense of the planet's high-speed rotation [1].

Sources

  1. [1] FUNDAMENTALS OF PHYSICAL GEOGRAPHY, Geography Class XI (NCERT 2025 ed.) > Chapter 9: Atmospheric Circulation and Weather Systems > Forces Affecting the Velocity and Direction of Wind > p. 78
  2. [2] https://www.science.gov/topicpages/e/earth+rotation+observations
How others answered
Each bar shows the % of students who chose that option. Green bar = correct answer, blue outline = your choice.
Community Performance
Out of everyone who attempted this question.
33%
got it right
✓ Thank you! We'll review this.

SIMILAR QUESTIONS

5 Cross-Linked PYQs

UPSC repeats concepts across years. Login to see how this question connects to 5 others.

Login with Google