JEE Mains · Physics · STD 11 - 1. units,dimensions and measurement
A student in the laboratory measures thickness of a wire using screw gauge. The readings are \(1.22\,mm , 1.23\,mm , 1.19\,mm\) and \(1.20\,mm\). The percentage error is \(\frac{ x }{121} \%\). The value of \(x\) is ..............
- A \(100\)
- B \(150\)
- C \(98\)
- D \(140\)
Answer & Solution
Correct Answer
(B) \(150\)
Step-by-step Solution
Detailed explanation
\(X =\frac{1.22 mm +1.23 mm +1.19 mm +1.20 mm }{4}\) \(X =1.21 mm\) \(\Delta x =\frac{0.01+0.02+0.02+0.01}{4}=\frac{0.06}{4}=0.015\) Percentage error \(=\frac{0.015}{1.21} \times 100\) \(X =150\)
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