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GS Paper IUPSC Prelims 1999
Health & Medicine
Question No. 487Interactive Test Mode
00:00
+2-0.66

Q487. Endoscopy, a technique used to explore the stomach or other inner parts of the body is based on the phenomenon of:

Endoscopy, a technique used to explore the stomach or other inner parts of the body is based on the phenomenon of:

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 1999 • Science and Technology

Correct Answer: Option (A) — Total internal reflection

Concept & Option Breakdown

Standard Reference Verified

Endoscopes utilize optical fiber bundles to transmit light and images into and out of internal organs. Optical fibers work on the principle of total internal reflection (TIR), where light reflects completely within the dense core when incident at an angle greater than the critical angle.

Elimination Heuristic & Exam Approach

Fiber-optic devices and medical endoscopes fundamentally operate on Total Internal Reflection.

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Question Specifications & Syllabus Mapping

Examination & YearUPSC Civil Services Preliminary Examination 1999 (Q487)
Paper & Marking SchemeGS Paper I • 2 Marks (-0.66 Negative for incorrect response)
Syllabus Subject & TopicScience and Technology → Health & Medicine
Official Answer KeyOption (A) — Total internal reflection

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Frequently Asked Questions — UPSC Prelims 1999 Q487

What is the official answer for UPSC Prelims 1999 GS Paper I Question 487 (Science and Technology)?

The official UPSC answer key for this 1999 Science and Technology (Health & Medicine) question is Option (A): "Total internal reflection". Correct attempts carry 2 Marks with -0.66 Negative penalty for wrong answers.

Which UPSC Prelims syllabus topic does this 1999 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?

Fiberoptic devices and medical endoscopes fundamentally operate on Total Internal Reflection.

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