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GS Paper IUPSC Prelims 2002
Health & Medicine
Question No. 261Interactive Test Mode
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Q261. Consider the following natural phenomena: 1. Terrestrial heating 2. Reflection of light 3. Refraction of light 4. Diffraction of light Due to which of these phenomena is a mirage formed?

Consider the following natural phenomena:

  1. Terrestrial heating
  2. Reflection of light
  3. Refraction of light
  4. Diffraction of light

Due to which of these phenomena is a mirage formed?

Select the correct option below (or cross out options to eliminate)
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Official Answer Key & Detailed Solution

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Official UPSC Answer KeyUPSC Prelims 2002 • Science and Technology

Correct Answer: Option (C) — 1 and 3

Concept & Option Breakdown

Standard Reference Verified

A mirage is an optical illusion caused by intense terrestrial heating of the ground, which creates steep temperature and density gradients in the overlying air. Light rays passing through these layers undergo continuous refraction (and total internal reflection near the critical boundary), bending the light rays upward to create the illusion of an inverted reflection or water surface.

Elimination Heuristic & Exam Approach

Mirages require ground heating (1) and continuous bending/refraction (3) through air layers of varying density.

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Question Specifications & Syllabus Mapping

Examination & YearUPSC Civil Services Preliminary Examination 2002 (Q261)
Paper & Marking SchemeGS Paper I • 2 Marks (-0.66 Negative for incorrect response)
Syllabus Subject & TopicScience and Technology → Health & Medicine
Official Answer KeyOption (C) — 1 and 3

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Frequently Asked Questions — UPSC Prelims 2002 Q261

What is the official answer for UPSC Prelims 2002 GS Paper I Question 261 (Science and Technology)?

The official UPSC answer key for this 2002 Science and Technology (Health & Medicine) question is Option (C): "1 and 3". Correct attempts carry 2 Marks with -0.66 Negative penalty for wrong answers.

Which UPSC Prelims syllabus topic does this 2002 question belong to?

This question belongs to GS Paper I under the subject "Science and Technology" and micro-topic "Health & Medicine". You can explore all repeated questions from Health & Medicine in Acme AI's 3D Prelims PYQ Realm or practice 50 full-length and sectional tests in the APT Prelims Test Series.

How can I solve this Health & Medicine UPSC Prelims question using option elimination?

Mirages require ground heating (1) and continuous bending/refraction (3) through air layers of varying density.

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