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A metre scale is graduated at every millimetre. How many significant digits will be there in a length measurement with this scale?

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#### Solution

The metre scale is graduated at every millimetre.

i.e., 1 m = 1000 mm

The minimum number of significant digits may be one (e.g., for measurements like 4 mm and 6 mm) and the maximum number of significant digits may be 4 (e.g., for measurements like 1000 mm). Hence, the number of significant digits may be 1, 2, 3 or 4.

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