Question

Given the numbers: \[161{\text{ }}cm;{\text{ }}0.161{\text{ }}cm;{\text{ }}0.0161{\text{ }}cm\]. The number of significant figure for three numbers is:
A. 3,4 and $5$
B. 3,3 and $3$
C. 3,3 and $4$
D. 3,4 and $4$

Answer 1

Hint- We will use the definition to solve these problems as all non-zero digits are significant and the zeros at the beginning of a number are not significant, so we will find the appropriate answer according to this definition.

Complete step-by-step answer:
Given numbers are \[161{\text{ }}cm;{\text{ }}0.161{\text{ }}cm;{\text{ }}0.0161{\text{ }}cm\]
As we know that
$(1)$ All non zero digits are significant.
 $(2)$ Non zero digits to the right of the decimal point are significant.
$(3)$ Zeroes to the left of the first non-zero digits in a number are not significant

Therefore, the number of significant figures for the numbers \[161{\text{ }}cm,{\text{ }}0.161{\text{ }}cm,{\text{ }}0.0161{\text{ }}cm\]
are same i.e. $3$,
Hence the correct answer is option B

Note-It is claimed that a quantity that doesn't equal zero is nonzero. A real nonzero number must be either positive or negative, and a complex nonzero number may have a nonzero component, either real or imaginary.