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GS Paper IUPSC Prelims 1997
Health & Medicine
Question No. 239Interactive Test Mode
00:00
+2-0.66

Q239. The working principle of a washing machine is:

The working principle of a washing machine is:

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 1997 • Science and Technology

Correct Answer: Option (A) — Centrifugation

Concept & Option Breakdown

Standard Reference Verified

Option (a) is correct: The working principle of a washing machine's spin dryer is centrifugation. Rapid spinning forces denser water molecules away from clothes via centrifugal effect, draining the water out through the perforations of the drum. Option (b) is used in medical kidney treatments. Option (c) is used in water purification and desalination. Option (d) is the passive movement of particles down a concentration gradient.

Elimination Heuristic & Exam Approach

Spinning drums use rotational centrifugal acceleration to separate liquid from solid fabric.

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Question Specifications & Syllabus Mapping

Examination & YearUPSC Civil Services Preliminary Examination 1997 (Q239)
Paper & Marking SchemeGS Paper I • 2 Marks (-0.66 Negative for incorrect response)
Syllabus Subject & TopicScience and Technology → Health & Medicine
Official Answer KeyOption (A) — Centrifugation

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Frequently Asked Questions — UPSC Prelims 1997 Q239

What is the official answer for UPSC Prelims 1997 GS Paper I Question 239 (Science and Technology)?

The official UPSC answer key for this 1997 Science and Technology (Health & Medicine) question is Option (A): "Centrifugation". Correct attempts carry 2 Marks with -0.66 Negative penalty for wrong answers.

Which UPSC Prelims syllabus topic does this 1997 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?

Spinning drums use rotational centrifugal acceleration to separate liquid from solid fabric.

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