Question

A cube has a side of length $1.2\times 10^{-2}m$. Calculate its volume.

• A. $1.7\times 10^{-6}{m}^3$
• B. $1.73\times 10^{-6}{m}^3$
• C. $1.70\times 10^{-6}{m}^3$
• D. $1.732\times 10^{-6}{m}^3$

Answer 1

Answer: (A)

Length of the cube, $L=1.2\times 10^{-2}m$
$\therefore$ Volume of the cube,
$V=L^3=\left(1.2\times 10^{-2}\right)\times \left(1.2\times 10^{-2}\right)\times \left(1.2\times 10^{-2}\right)m^3$
$\Rightarrow V=1.728\times 10^{-6}{m}^3$
But as the length contains only $2$ significant digits,
thus volume must also contain $2$ significant digits.
Hence, volume of the cube is $1.7\times 10^{-6}{m}^3$