Question

The length, breadth and thickness of a block are given by $l=12\, cm,\, b=6\, cm$ and $t=2.45\, cm$. The volume of the block according to the idea of significant figures should be :

• A. $1\times 10^{2}cm^{3}$
• B. $2\times 10^{2}cm^{3}$
• C. $1.763\times 10^{2}cm^{2}$
• D. none of these

Answer 1

Answer: (B)

$2\times 10^{2}cm^{3}$

Answer 2

Using the relation for volume $V =$ length $\times$ breadth $\times$ thickness $=12 \times 6 \times 245$ $=176.4\, cm ^{3}$ $=1.764 \times 10^{2} cm ^{3}$ The minimum number of significant figures is 1 in breadth. Hence, the volume will contain only one significant figure. Therefore, $V=2 \times 10^{2} cm ^{3} .$