The number of significant figures in 0.02040 is MCQ with Answer and Explanation

The number of significant figures in 0.02040 is
A. 2
B. 3
C. 5
D. 4
Answer: Option D
Solution (By JKExamLibrary)
Leading zeros not significant. '2040' – trailing zero after decimal is significant. So digits 2,0,4,0 are significant = 4. Rule: zeros between non-zero and trailing zeros after decimal count.

This question belongs to: Science Physics

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Correct Answer: Option B


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This question belongs to: Science Physics
Question #2 Report Error
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Correct Answer: Option C


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Question #3 Report Error
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Correct Answer: Option C


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Kinetic energy KE = p²/(2m), where p is momentum. Thus p = √(2m·KE). If KE becomes 4 times, p_new = √(2m·4KE) = 2√(2m·KE) = 2p_initial. Hence momentum doubles. This relationship shows momentum scales with square root of kinetic energy for constant mass. Memory tip: p ∝ √KE when mass constant. This conceptual link between momentum and kinetic energy is frequently tested in competitive exams to assess depth of understanding beyond rote formula memorization. Always derive relationships when direct formulas aren't recalled.

This question belongs to: Science Physics