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GS Paper IUPSC Prelims 2001
Health & Medicine
Question No. 253Interactive Test Mode
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Q253. Assertion (A): Radio waves bend in a magnetic field. Reason (R): Radio waves are electromagnetic in nature.

Assertion (A): Radio waves bend in a magnetic field. Reason (R): Radio waves are electromagnetic in nature.

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Official Answer Key & Detailed Solution

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Official UPSC Answer KeyUPSC Prelims 2001 • Science and Technology

Correct Answer: Option (D) — A is false but R is true

Concept & Option Breakdown

Standard Reference Verified

Assertion (A) is false: Electromagnetic waves, including radio waves, consist of oscillating electric and magnetic fields and carry no net charge. Hence, they are not deflected or bent by external static magnetic or electric fields. Reason (R) is true: Radio waves are indeed transverse electromagnetic waves with wavelengths ranging from millimeters to kilometers.

Elimination Heuristic & Exam Approach

Static magnetic fields exert force only on moving electric charges (Lorentz force, F = q(v × B)). Photons have zero charge (q = 0), so electromagnetic waves do not bend in a magnetic field.

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Question Specifications & Syllabus Mapping

Examination & YearUPSC Civil Services Preliminary Examination 2001 (Q253)
Paper & Marking SchemeGS Paper I • 2 Marks (-0.66 Negative for incorrect response)
Syllabus Subject & TopicScience and Technology → Health & Medicine
Official Answer KeyOption (D) — A is false but R is true

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Frequently Asked Questions — UPSC Prelims 2001 Q253

What is the official answer for UPSC Prelims 2001 GS Paper I Question 253 (Science and Technology)?

The official UPSC answer key for this 2001 Science and Technology (Health & Medicine) question is Option (D): "A is false but R is true". Correct attempts carry 2 Marks with -0.66 Negative penalty for wrong answers.

Which UPSC Prelims syllabus topic does this 2001 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?

Static magnetic fields exert force only on moving electric charges (Lorentz force, F = q(v × B)). Photons have zero charge (q = 0), so electromagnetic waves do not bend in a magnetic field.

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