The length and breadth of a rectangular sheet are 5 mm and 2.5 mm, measured with a screw gauge of pitch 0.75 mm and 15 circular-scale divisions. Find the maximum possible error in its area.
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The length and breadth of a rectangular sheet are 5 mm and 2.5 mm, measured with a screw gauge of pitch 0.75 mm and 15 circular-scale divisions. Find the maximum possible error in its area.

G1 Physics · Accepted Answer

Least count=0.75/15=0.05 mm. For S=lb, maximum \fractional \fractional \fractional error ΔS/S=Δl/l+Δb/b=0.05/5+0.05/2.5=0.03. Since S=12.5 mm², ΔS=0.03×12.5=0.375 mm².