JEE Mains · Physics · STD 11 - 1. units,dimensions and measurement
A tiny metallic rectangular sheet has length and breadth of 5 mm and 2.5 mm , respectively. Using a specially designed screw gauge which has pitch of 0.75 mm and 15 divisions in the circular scale, you are asked to find the area of the sheet. In this measurement, the maximum fractional error will be \(\frac{x}{100}\) where \(x\) is _________.
- A 5
- B 3
- C 4
- D 2
Answer & Solution
Correct Answer
(B) 3
Step-by-step Solution
Detailed explanation
Since least count of the instrument can be calculated as \(\begin{aligned} & \text { Least count }=\frac{\text { pitch length }}{\text { No. of division on circular scale }} \\ & =\frac{0.75}{15}=0.05 \mathrm{~mm} . \end{aligned}\) Here we are provided…
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