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. $1.728\times {10}^{-6}{m}^3$

Answer 1

The correct option is A $1.7\times {10}^{-6}{m}^3$

Length of the cube, $L=1.2\times {10}^{-2}m$

$\therefore$ Volume of the cube, $V=L^3=(1.2\times {10}^{-2})$ $\times (1.2\times {10}^{-2})$ $\times (1.2\times {10}^{-2})m^3$

$⟹V=1.728\times {10}^{-6}{m}^3$

But as the length contains only $2$ significant digits, thus volume must also contain $2$ significant digits.

Hence, volume of the cube is $1.7\times {10}^{-6}{m}^3$