Significant figures are the meaningful digits in a measured quantity. They indicate the precision of a measurement.
Significant figures include:
All non-zero digits are significant.
Example: 234 → 3 significant figures
Zeros between non-zero digits are always significant.
Example: 1002 → 4 significant figures
Zeros before non-zero digits are not significant.
Example: 0.005 → 1 significant figure
Trailing zeros are significant only if a decimal point is present.
Example: 150 → 2 significant figures 150.0 → 4 significant figures
The result should have the same number of decimal places as the least precise value.
The result should have the same number of significant figures as the least precise value.
If the digit to be dropped is less than 5, leave the preceding digit unchanged. If it is 5 or more, increase the preceding digit by 1.
Q1. Number of significant figures in 0.0045 is: A) 1 B) 2 C) 3 D) 4 Answer: B Q2. How many significant figures are there in 1200? A) 1 B) 2 C) 3 D) 4 Answer: B Q3. Number of significant figures in 1200.0 is: A) 2 B) 3 C) 4 D) 5 Answer: C Q4. Zeros between non-zero digits are: A) Never significant B) Sometimes significant C) Always significant D) Significant only with decimal Answer: C Q5. Result of multiplication should contain: A) Maximum significant figures B) Minimum significant figures C) Average significant figures D) No significant figures Answer: B
Significant figures represent the precision of a measurement.
