Question

Find the number of significant figures in the given data
$\begin{array}{cc}\text{P)}0.543& \text{U)}3\\ \text{Q)}4.330& \text{V) 4}\\ \text{R)}1.32\times {10}^{-2}& \text{W)}5\\ \text{S)}0.002& \text{X)}1\end{array}$

• A. p-u, q-u, r-u, s-u
• B. p-u, q-u, r-u, s-x
• C. p-v, q-v, r-u, s-u
• D. p-v, q-v, r-u, s-v

Answer 1

The correct option is B

p-u, q-u, r-u, s-x

(a) 0.543 :- 3 significant figures.

Leading zeroes are not significant

(b) 4.330 :- 4 significant figure

Trailing zeroes are significant

(c) $1.32\times {10}^{-2}$ :-3 significant figures

Exponential notation does not affect the significant figures.

Alternate solution: Write in scientific notation and count.

$0.543=5.43\times {10}^{-1}$ so only 3 significant figure

$4.330=4.330\times {10}^0$ so 4 significant figure

$1.32\times {10}^{-2}=1.32\times {10}^{-2}$ so 3 significant figure

$0.002=2\times {10}^{-3}$ so 1 significant figure