JEE Main · 2021 · 25 Jul 2021 · Shift 2 · Some Basic Concepts of Chemistry

The number of significant figure in 0.00340 is ____.

Answer: 3

Solution

Zeros written only to place the decimal point are not significant, so the three zeros at the front of 0.00340 are not counted. The digits 3 and 4 are significant, and the final zero is significant as well, because a trailing zero to the right of the decimal point is written only to record the precision of the measurement and would be omitted otherwise. The number 0.00340 therefore has 3 significant figures.

JEE Main · 2021 · 25 Jul 2021 · Shift 2 · Integer answer

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