The percentage error in measurement of a cube's side is 2%. Maximum percentage error in its volume is: MCQ with Answer and Explanation

The percentage error in measurement of a cube's side is 2%. Maximum percentage error in its volume is:
A. 8%
B. 6%
C. 2%
D. 4%
Answer: Option B
Solution (By JKSSB Mock Tests)
Volume V = a³. For error propagation: % error in V = 3 × % error in a. Given 2% error in side, volume error = 3×2% = 6%. Power rule: if Q = xⁿ, %ΔQ = |n|×%Δx. Memory tip: Volume depends on cube of length ⇒ errors triple. Common in experimental error analysis questions.

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A body of mass 2 kg has momentum 10 kg m/s. Its kinetic energy is
A. 5 J
B. 20 J
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Correct Answer: Option C


Explanation:
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Correct Answer: Option A


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