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GS Paper IUPSC Prelims 2009
Health & Medicine
Question No. 252Interactive Test Mode
00:00
+2-0.66

Q252. Which one of the following types of waves are used in a night vision apparatus?

Which one of the following types of waves are used in a night vision apparatus?

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 2009 • Science and Technology

Correct Answer: Option (C) — Infra-red waves

Concept & Option Breakdown

Standard Reference Verified

Night vision and thermal imaging apparatus detect infrared radiation emitted by objects as heat. Warm bodies emit significant amounts of infrared radiation, which can be captured and converted into visible electronic images.

Elimination Heuristic & Exam Approach

Night vision is based on thermal radiation detection; heat radiation corresponds to the infrared band of the electromagnetic spectrum.

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Question Specifications & Syllabus Mapping

Examination & YearUPSC Civil Services Preliminary Examination 2009 (Q252)
Paper & Marking SchemeGS Paper I • 2 Marks (-0.66 Negative for incorrect response)
Syllabus Subject & TopicScience and Technology → Health & Medicine
Official Answer KeyOption (C) — Infra-red waves

Related & Repeated Prelims PYQs (2)

Questions from other UPSC Prelims years testing the same or closely linked concept.

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2000 • Q28987% Match

Which one of the following does a TV remote control unit use to operate a TV set?

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2007 • Q28480% Match

Which of the following types is used by computed tomography employed for visualisation of the internal structure of the human body?

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Frequently Asked Questions — UPSC Prelims 2009 Q252

What is the official answer for UPSC Prelims 2009 GS Paper I Question 252 (Science and Technology)?

The official UPSC answer key for this 2009 Science and Technology (Health & Medicine) question is Option (C): "Infra-red waves". Correct attempts carry 2 Marks with -0.66 Negative penalty for wrong answers.

Which UPSC Prelims syllabus topic does this 2009 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?

Night vision is based on thermal radiation detection; heat radiation corresponds to the infrared band of the electromagnetic spectrum.

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