Question

The number of significant figures in the measurement of 45.030 mm is?

1) none
2) three
3) four
4) five
5) six

Answer 1

The number 45.030 mm has five significant figures, with all digits being significant due to the presence of non-zero numbers and trailing zeros after the decimal point.

Step-by-step explanation:

The measurement of 45.030 mm has five significant figures. This is because, according to the rules for determining significant figures:

• All non-zero digits are considered significant (rule 1).
• Any zeros between significant figures are also significant (rule 2).
• Trailing zeros to the right of the decimal point are significant (rule 5).

Therefore, in 45.030, the '4' and '5' are non-zero digits and thus significant, the '0' in between '5' and '3' is counted as it falls between significant figures, and the final two '0's are also counted because they are trailing zeros to the right of the decimal point. This leads to a total of five significant figures.